Merge remote-tracking branch 'origin/master' into xtr/trajectory-timeline

# Conflicts: # apps/web/tests/code-mode-fixture.snapshot.ts # apps/web/tests/navigation-panes.e2e.ts # apps/web/tests/snapshots/navigation-panes/details-open.expected.md # packages/client/runtime/src/client/index.ts # packages/client/runtime/src/client/sessions/fold-adapter.ts # packages/client/ui-trajectory/tests/views.spec.tsx
2026-07-28 18:06:04 +08:00
parent bbd9949d31 817c09828b
commit 0e1e594314
185 changed files with 4826 additions and 966 deletions
--- a/packages/client/runtime/package.json
+++ b/packages/client/runtime/package.json
@@ -32,10 +32,13 @@
  "license": "BSD-3-Clause",
  "dependencies": {
    "@deepseek-ai/dsh-client-connection": "workspace:^",
+    "@deepseek-ai/dsh-commands": "workspace:^",
    "@deepseek-ai/dsh-client-ui-slots": "workspace:^",
    "@deepseek-ai/dsh-host-apiproxy": "workspace:^",
    "@deepseek-ai/dsh-llm": "workspace:^",
    "@deepseek-ai/dsh-session": "workspace:^",
+    "@deepseek-ai/dsh-session-projection": "workspace:^",
+    "@deepseek-ai/dsh-session-title": "workspace:^",
    "immer": "^10.1.1",
    "react": "^18.2.0",
    "zustand": "~4.4.7"
--- a/packages/client/runtime/src/client/index.ts
+++ b/packages/client/runtime/src/client/index.ts
@@ -7,6 +7,7 @@ import { SessionsService } from './sessions/service.ts'
 import type { SessionListState } from './sessions/service.ts'
 import { WorkspacesService } from './workspaces/service.ts'
 import type { ConversationSnapshot, RunningToolCall, ToolResultNode } from './sessions/conversation.ts'
+import type { UseProjection } from './sessions/projection-store.ts'

 export { SlotsService } from './slots.ts'
 export type { RootOwnerProps } from './slots.ts'
@@ -29,7 +30,7 @@ export type {
 } from './contract/store.ts'
 export type {
  AssistantBlock, AssistantMessageNode, AssistantProvenanceView, AssistantRequestConfig,
-  AssistantTiming, CodeSubCall, ComposerPhase, ContextMessageNode, ConversationNode,
+  AssistantTiming, CodeSubCall, CommandNode, ComposerPhase, ContextMessageNode, ConversationNode,
  ConversationSnapshot, QueuedMessage, RunningToolCall,
  SteeringMessageNode, TodoItem, ToolResultNode, UnknownSurfaceNode, UserMessageNode,
 } from './sessions/conversation.ts'
@@ -43,6 +44,11 @@ export type { ConversationHistoryProjection } from './sessions/fold-adapter.ts'
 export type { SessionHistoryInspection } from './sessions/history.ts'
 export { PendingWait } from './sessions/pending.ts'
 export type { PendingInteraction, PendingKind, PendingPayloads } from './sessions/pending.ts'
+// Projection value store (session-projection RFC, push model): host-computed
+// whole values per key; domains ship projection support with zero client code.
+export type {
+  ProjectionsBaseline, ProjectionValueStore, SessionProjectionMap, UseProjection,
+} from './sessions/projection-store.ts'
 export type { SessionId } from '@deepseek-ai/dsh-client-connection/client'

 /** Client-side Cordis context after declaration merging. */
@@ -68,12 +74,16 @@ declare module '@deepseek-ai/dsh-client-ui-slots' {
    useSession: SnapshotSelectorHook<ConversationSnapshot>
    /** The framework-resolved session id (owners never pass it). */
    sessionId: SessionId
+    /** The fifth framework hook seat: key-addressed projection reader (undefined = capability absent). */
+    useProjection: UseProjection
  }
  /** Standard kit for slots that remain mounted while current session changes. */
  interface SessionMaybeStandardProps {
    useSession: MaybeSnapshotSelectorHook<ConversationSnapshot>
    /** Current session id; absent in the no-session state. */
    sessionId: SessionId | undefined
+    /** Key-addressed projection reader; every key reads absent while no session is current. */
+    useProjection: UseProjection
  }
  /** Props injected into every global slot component. */
  interface GlobalStandardProps {
--- a/packages/client/runtime/src/client/sessions/conversation.ts
+++ b/packages/client/runtime/src/client/sessions/conversation.ts
@@ -3,6 +3,7 @@
 // substructures keep their references (the React.memo premise). callId/approvalId stay plain
 // string here (narrow to real brands when convenient).

+import type { CommandId } from '@deepseek-ai/dsh-commands/brand'
 import type { ContentBlock } from '@deepseek-ai/dsh-llm/types'
 import type { TodoItem } from '@deepseek-ai/dsh-session/types'
 import type {
@@ -152,6 +153,31 @@ export interface UnknownSurfaceNode {
  data: unknown
 }

+/**
+ * One slash-command lifecycle folded from the log-only `command/run` /
+ * `command/done` pair (paired by commandId, mirroring tool call↔result).
+ * Log-only events never enter the surface fold, so the FoldAdapter indexes
+ * them separately and merges the nodes into the flow by seq. A window cut
+ * between the pair soft-falls like tool pairs: a done with no in-window run
+ * still builds a node (name/args null), and a run with no done renders as
+ * still executing.
+ */
+export interface CommandNode {
+  kind: 'command'
+  /** Seq of the command/run event; the done event's seq when only the done is in-window. */
+  seq: number
+  /** Unix epoch ms of the anchoring event. */
+  time: number
+  /** Pairing id minted by the host executor. */
+  commandId: CommandId
+  /** Command name (run payload's structured field); null when the run fell outside the window. */
+  name: string | null
+  /** Verbatim rawInput after the name, separator whitespace included (run payload); null when the run fell outside the window. */
+  args: string | null
+  /** Settlement outcome (done payload); null while the command is still executing. */
+  outcome: { kind: 'success' | 'error'; text?: string } | null
+}
+
 /** Finalized conversation node union (kind discriminates; seq is the React key). */
 export type ConversationNode =
  | UserMessageNode
@@ -159,6 +185,7 @@ export type ConversationNode =
  | SteeringMessageNode
  | ContextMessageNode
  | ToolResultNode
+  | CommandNode
  | UnknownSurfaceNode

 /**
@@ -277,7 +304,4 @@ export interface ConversationSnapshot {
   */
  blank: boolean
  lastAgentError: string | null
-  /** Current whole-list `todo/write` projection — the tail page's full-log value, then each live
-   *  write (last write wins); empty = the log holds no plan. */
-  todos: readonly TodoItem[]
 }
--- a/packages/client/runtime/src/client/sessions/fold-adapter.ts
+++ b/packages/client/runtime/src/client/sessions/fold-adapter.ts
@@ -10,11 +10,12 @@ import type { SessionEvent } from '@deepseek-ai/dsh-session/types'
 import {
  SurfaceManager, isSurfaceEligibleType, isSurfaceEvent,
 } from '@deepseek-ai/dsh-session/surface'
+import type { CommandId } from '@deepseek-ai/dsh-commands/brand'
 import type {
  HistoryEntry, ToolCallView, ToolEventView, ToolResultView,
 } from '@deepseek-ai/dsh-client-connection/client'
 import type {
-  AssistantRequestConfig, AssistantTiming, ConversationNode,
+  AssistantRequestConfig, AssistantTiming, CommandNode, ConversationNode,
 } from './conversation.ts'
 import { toAssistantBlocks } from './conversation.ts'
 import type {
@@ -182,6 +183,15 @@ export class FoldAdapter {
  private callIdx = new Map<string, CallIndexEntry>()
  /** Wire result views keyed by the tool/result event's seq (views ride the envelope, not the event). */
  private resultViews = new Map<number, ToolResultView>()
+  /**
+   * Command lifecycle nodes by commandId (insertion = run order). The
+   * `command/run`/`command/done` pair is log-only, so the surface fold never
+   * emits it; this index folds the pair (done settles its run's node in
+   * place) and nodes() merges the products into the flow by seq. Window cuts
+   * soft-fall like tool pairs: a done with no in-window run still builds a
+   * node.
+   */
+  private commandIdx = new Map<string, CommandNode>()
  /** Window revision (bumped on reset/append) keying the nodes() result cache: an unchanged
   *  window returns the previous ARRAY reference, not just cached elements — the snapshot's
   *  reference-stability contract (§A.9.4) starts here. */
@@ -228,12 +238,14 @@ export class FoldAdapter {
    this.contextGeneration = 0
    this.activePrompt = undefined
    this.promptsByContext = new Map()
+    this.commandIdx = new Map()
    for (let i = 0; i < events.length; i++) {
      const event = events[i]
      /* v8 ignore next -- dense-array guard: i stays within events.length, so the undefined arm needs a sparse array no caller builds. */
      if (event !== undefined) {
        this.indexCall(event, views?.[i])
        if (this.projectContexts) this.indexContextPrompt(event)
+        this.indexCommand(event)
      }
    }
  }
@@ -252,6 +264,7 @@ export class FoldAdapter {
    this.padded.push(event)
    this.indexCall(event, view)
    if (this.projectContexts) this.indexContextPrompt(event)
+    this.indexCommand(event)
  }

  /**
@@ -279,7 +292,23 @@ export class FoldAdapter {
      /* v8 ignore next -- both seq sources only emit indexes present in padded. */
      if (node !== undefined) out.push(node)
    }
-    const value = { nodes: out, degraded: this.degraded }
+    // Command nodes fold outside the surface (log-only events); merge by seq.
+    // Both inputs are seq-ascending (surface order and run-index insertion
+    // order share the log order), so one linear merge keeps flow order.
+    let nodes = out
+    if (this.commandIdx.size > 0) {
+      nodes = []
+      const commands = [...this.commandIdx.values()]
+      let next = 0
+      for (const node of out) {
+        for (let cmd = commands[next]; cmd !== undefined && cmd.seq < node.seq; cmd = commands[++next]) {
+          nodes.push(cmd)
+        }
+        nodes.push(node)
+      }
+      for (let cmd = commands[next]; cmd !== undefined; cmd = commands[++next]) nodes.push(cmd)
+    }
+    const value = { nodes, degraded: this.degraded }
    this.nodesResult = { rev: this.rev, value }
    return value
  }
@@ -417,6 +446,36 @@ export class FoldAdapter {
    return undefined
  }

+  /** Fold one command lifecycle event into its node (run mints, done settles in place; done-only soft-falls). */
+  private indexCommand(event: SessionEvent): void {
+    // Log-only plugin events: the host-side dsh-commands declaration cannot
+    // enter the client program, so this wire consumer narrows structurally
+    // (the same posture as tool/code-dispatch in session.ts).
+    if ((event.type as string) === 'command/run') {
+      const data = event.data as unknown as { commandId: CommandId; name: string; args: string }
+      this.commandIdx.set(data.commandId, {
+        kind: 'command', seq: event.seq, time: event.time,
+        commandId: data.commandId, name: data.name, args: data.args, outcome: null,
+      })
+      return
+    }
+    if ((event.type as string) !== 'command/done') return
+    const data = event.data as unknown as { commandId: CommandId; kind: 'success' | 'error'; text?: string }
+    const run = this.commandIdx.get(data.commandId)
+    const outcome = { kind: data.kind, ...data.text === undefined ? {} : { text: data.text } }
+    if (run === undefined) {
+      // Cross-window cut: the run page fell out of the window — build the
+      // node from the done alone (same soft-fall as a call-less tool result).
+      this.commandIdx.set(data.commandId, {
+        kind: 'command', seq: event.seq, time: event.time,
+        commandId: data.commandId, name: null, args: null, outcome,
+      })
+      return
+    }
+    // Settle in place: a fresh node object (published references stay immutable).
+    this.commandIdx.set(data.commandId, { ...run, outcome })
+  }
+
  private indexCall(event: SessionEvent, view?: ToolEventView): void {
    if (event.type === 'tool/result') {
      if (view?.for === 'result') this.resultViews.set(event.seq, view.view)
--- a/packages/client/runtime/src/client/sessions/manager.ts
+++ b/packages/client/runtime/src/client/sessions/manager.ts
@@ -9,7 +9,12 @@ import { transportError } from '@deepseek-ai/dsh-host-apiproxy/api'
 import { mergeOrderedBaseline } from '../ordered-baseline.ts'
 import type { SessionListEntry, TitledSessionSummary } from './lineage.ts'
 import { flattenLineage } from './lineage.ts'
+// Type-only merge edge: the title domain's client-namespace outlet declares
+// the 'title' projection key this manager projects into list rows (and any
+// useProjection('title') consumer reads). Zero value imports by construction.
+import type {} from '@deepseek-ai/dsh-session-title/client'
 import { Notifier } from './notifier.ts'
+import { ProjectionValueStore } from './projection-store.ts'
 import { Session } from './session.ts'

 /**
@@ -43,12 +48,6 @@ type SessionListMutation =
 /** Per-session cap for pre-instantiation approval/question buffering (low-frequency frames; a few dozen covers any real backlog). */
 const PENDING_BUFFER_CAP = 32

-/** Latest title control snapshot retained independently of list/instance arrival. */
-interface SessionTitleSnapshot {
-  title: string
-  eventSeq: number
-  updatedAt: number
-}

 /** Instance cluster + frame entry + the session list (see the web client architecture RFC). */
 export class SessionManager {
@@ -58,7 +57,11 @@ export class SessionManager {
   *  drop-and-backfill path; replayed and cleared on instantiation. Bounded per session (these
   *  frames are low-frequency; overflow drops oldest) and dropped on session-removed (audit S7). */
  private readonly pendingBuffers = new Map<SessionId, RpcRequest<MuxFrame>[]>()
-  private readonly titleSnapshots = new Map<SessionId, SessionTitleSnapshot>()
+  /** Per-session projection value stores, retained independently of instance arrival (the
+   *  title-snapshot precedent, generalized): push frames land here whether or not the Session
+   *  is instantiated (list rows read the 'title' key), and an instantiated Session adopts the
+   *  same store so history-baseline seeding and frames converge on one row set. */
+  private readonly projectionStores = new Map<SessionId, ProjectionValueStore>()
  private summaries: SessionSummary[] = []
  private listState: 'idle' | 'loading' | 'error' = 'idle'
  /** Arrival phase; the pending → ready edge fires on the first successful pull (see SessionListPhase). */
@@ -163,9 +166,23 @@ export class SessionManager {
      onEngaged: (engaged) => {
        this.recordMutation({ kind: 'engaged', sessionId: engaged.sessionId })
      },
+      projections: this.projectionStore(sessionId),
    })
  }

+  /** Resident per-session projection store (create-on-demand; outlives instantiation). */
+  private projectionStore(sessionId: SessionId): ProjectionValueStore {
+    let store = this.projectionStores.get(sessionId)
+    if (store === undefined) {
+      store = new ProjectionValueStore()
+      // List rows project off store keys (title); any-key changes re-enter
+      // the manager's own batched rebuild channel.
+      store.subscribeAny(() => { this.notifier.markDirty() })
+      this.projectionStores.set(sessionId, store)
+    }
+    return store
+  }
+
  // ---- List surface ----

  /** Full refresh via session.list (single-flight: an in-flight call is reused). */
@@ -302,23 +319,20 @@ export class SessionManager {
  handleMuxEnvelope(envelope: RpcRequest<MuxFrame>): void {
    const frame = envelope.payload
    if (frame.type === 'stream/error') return // Controller already treats this as stream failure
-    if (frame.type === 'session/title') {
-      const current = this.titleSnapshots.get(frame.sessionId)
-      if (current !== undefined && current.eventSeq >= frame.eventSeq) return
-      this.titleSnapshots.set(frame.sessionId, {
-        title: frame.title,
-        eventSeq: frame.eventSeq,
-        updatedAt: frame.updatedAt,
-      })
+    if (frame.type === 'session/projection') {
+      // Finished host-computed value: land it in the resident store whether or
+      // not the Session is instantiated (list rows read the 'title' key). The
+      // synchronous markDirty keeps the list snapshot same-tick fresh (the
+      // store's own any-key channel is microtask-batched).
+      this.projectionStore(frame.sessionId).apply(frame.key, frame.value, frame.seq)
      this.notifier.markDirty()
      return
    }
    if (frame.type === 'session/subscribed') {
-      const current = this.titleSnapshots.get(frame.sessionId)
-      if (current !== undefined && current.eventSeq > frame.lastSeq) {
-        this.titleSnapshots.delete(frame.sessionId)
-        this.notifier.markDirty()
-      }
+      // Rows past the host's durable baseline rode state a restart lost; drop
+      // them so last-wins cannot pin a phantom value over recomputed truth.
+      this.projectionStores.get(frame.sessionId)?.truncate(frame.lastSeq)
+      this.notifier.markDirty()
      // New mux-generation baseline: buffered session/queued frames belong to
      // the previous generation and the host is about to resend the live
      // snapshot — drop them, or every reconnect appends a duplicate batch
@@ -377,7 +391,7 @@ export class SessionManager {
        this.recordMutation({ kind: 'remove', sessionId: frame.sessionId })
        this.sessions.get(frame.sessionId)?.handleRemoved() // instance survives (resident-instance rule), only flagged in the snapshot
        this.pendingBuffers.delete(frame.sessionId) // a removed session's buffered frames must not replay on a future instantiation
-        this.titleSnapshots.delete(frame.sessionId)
+        this.projectionStores.delete(frame.sessionId) // removed sessions drop their projection rows with the instance
        return
      }
      case 'host/session-status': {
@@ -402,10 +416,12 @@ export class SessionManager {

  private buildListSnapshot(): SessionListSnapshot {
    const merged: TitledSessionSummary[] = this.summaries.map((summary) => {
-      const title = this.titleSnapshots.get(summary.sessionId)
-      return title === undefined
-        ? summary
-        : { ...summary, title: title.title, updatedAt: Math.max(summary.updatedAt, title.updatedAt) }
+      // List rows read the generic 'title' projection key (host-computed unit
+      // value; the bespoke session/title frame is retired).
+      const title = this.projectionStores.get(summary.sessionId)?.get('title')
+      return typeof title === 'string' && title !== ''
+        ? { ...summary, title }
+        : summary
    })
    const fresh = flattenLineage(merged)
    const items = fresh.map((entry) => {
--- a/packages/client/runtime/src/client/sessions/projection-store.ts
+++ b/packages/client/runtime/src/client/sessions/projection-store.ts
@@ -0,0 +1,183 @@
+/**
+ * Generic per-session projection value store (session-projection RFC, push
+ * model): the host is the only computation site; the client holds finished
+ * whole values per key — `key → { value, seq }` — seeded by the history tail
+ * page's projections block and updated by `session/projection` push frames,
+ * under the single rule **higher seq wins**. No client-side domain folding
+ * exists: a domain ships projection support with zero client code. Per-key
+ * bare observable faces feed `useProjection` (web-react binds them).
+ */
+import type { SessionProjectionMap } from '@deepseek-ai/dsh-session-projection/types'
+import type { ObservableSnapshot } from '../contract/store.ts'
+import { Notifier } from './notifier.ts'
+
+// The single projection type table, typed end to end (host unit, wire block,
+// client store, React hook) — the interface package's pure-type outlet
+// (`/types`, zero imports), never the package root: the root's dsh-agent →
+// dsh-session chain would drag the host `Context.sessions` merge into the
+// client program (one program must not hold both sides). No second
+// client-side "views" table (user ruling, RFC Alternatives).
+export type { SessionProjectionMap } from '@deepseek-ai/dsh-session-projection/types'
+
+/**
+ * The fifth framework hook seat (session-projection RFC): key-addressed
+ * projection reader delivered through the standard kit. `undefined` uniformly
+ * means capability absent — host unit unmounted, or no baseline/frame has
+ * carried the key yet. The selector overload mirrors useSession (per-key uSES
+ * binding; reference stability holds because a key's value reference changes
+ * only when a frame or baseline lands).
+ */
+export type UseProjection = {
+  <K extends Extract<keyof SessionProjectionMap, string>>(key: K): SessionProjectionMap[K] | undefined
+  <K extends Extract<keyof SessionProjectionMap, string>, S>(
+    key: K,
+    selector: (value: SessionProjectionMap[K] | undefined) => S,
+    eq?: (a: S, b: S) => boolean,
+  ): S
+}
+
+/**
+ * Tail-page projections baseline — structurally identical to the wire's
+ * `SessionProjectionsBlock` (apiproxy api layer), restated here so the
+ * React-free store depends only on the type table, not the wire package's
+ * response vocabulary.
+ */
+export interface ProjectionsBaseline {
+  /** The consistent-cut seq (equals the window tail seq by construction). */
+  asOfSeq: number
+  /** Whole current values by key; a registered key absent here means the capability is absent. */
+  values: Partial<SessionProjectionMap>
+}
+
+/** One key's row: the latest finished value and the seq it is consistent with. */
+interface Row {
+  value: unknown
+  seq: number
+}
+
+/** Per-key notification channel: the bare face plus its batching notifier. */
+interface Channel {
+  face: ObservableSnapshot<unknown>
+  notifier: Notifier
+}
+
+/**
+ * One session's projection values. Framework semantics, uniform across every
+ * key: a baseline seeds rows at its cut, a push frame updates one row, and in
+ * both paths a lower-or-equal seq loses — a replayed frame cannot regress a
+ * value, a stale baseline cannot overwrite a newer frame. A key the store has
+ * never seen reads `undefined` (capability absent). Faces are identity-stable
+ * per key (create-on-demand, cached) so the React side binds each exactly
+ * once; the store-level channel (`subscribeAny`) serves coarse consumers (the
+ * manager's list projection reads the `title` key).
+ */
+export class ProjectionValueStore {
+  private readonly rows = new Map<string, Row>()
+  private readonly channels = new Map<string, Channel>()
+  /** Coarse any-key channel (no snapshot cache to rebuild: reads hit rows directly). */
+  private readonly anyNotifier = new Notifier(() => {})
+
+  /**
+   * Key-addressed bare observable face (the useProjection resolution path).
+   * Always defined — absence is an `undefined` snapshot, never a missing
+   * face, so a component may subscribe before the key ever carries a value.
+   * @param key - projection key.
+   * @returns the identity-stable face for this key.
+   */
+  faceOf(key: string): ObservableSnapshot<unknown> {
+    return this.channel(key).face
+  }
+
+  /**
+   * Current whole value for a key (erased framework read; typed reads go
+   * through `useProjection`'s map lookup).
+   * @param key - projection key.
+   * @returns the value, or undefined while the key is absent.
+   */
+  get(key: string): unknown {
+    return this.rows.get(key)?.value
+  }
+
+  /**
+   * Subscribe to any-key changes (microtask-batched) — the manager's list
+   * rebuild channel.
+   * @param listener - change callback.
+   * @returns the unsubscribe function.
+   */
+  subscribeAny(listener: () => void): () => void {
+    return this.anyNotifier.subscribe(listener)
+  }
+
+  /**
+   * Apply one finished value (the `session/projection` push-frame path).
+   * @param key - projection key.
+   * @param value - whole value computed by the host unit.
+   * @param seq - the unit's watermark at emission.
+   */
+  apply(key: string, value: unknown, seq: number): void {
+    const row = this.rows.get(key)
+    if (row !== undefined && seq <= row.seq) return // higher seq wins; replays and stale frames drop
+    this.rows.set(key, { value, seq })
+    this.changed(key)
+  }
+
+  /**
+   * Seed from a history tail page's projections block: every carried key
+   * lands under the same seq rule as frames; a key the block omits is
+   * capability-absent as of the cut — its row clears unless a newer frame
+   * already superseded the cut (a stale baseline can neither overwrite nor
+   * clear newer values).
+   * @param baseline - the response's projections block.
+   */
+  seed(baseline: ProjectionsBaseline): void {
+    // Erased walk: the framework crosses the open key space; per-key typing
+    // is re-established at the consumer (useProjection's map lookup).
+    const values = baseline.values as Record<string, unknown>
+    for (const key of Object.keys(values)) this.apply(key, values[key], baseline.asOfSeq)
+    for (const [key, row] of this.rows) {
+      if (Object.hasOwn(values, key)) continue
+      if (row.seq > baseline.asOfSeq) continue
+      this.rows.delete(key)
+      this.changed(key)
+    }
+  }
+
+  /**
+   * Drop rows past a mux-generation baseline (`session/subscribed.lastSeq`):
+   * a row claiming knowledge beyond the host's own durable baseline rode
+   * state a restart lost — under last-wins it would wrongly outrank the
+   * host's recomputed (lower-seq) values forever. Durable replay and the next
+   * baseline re-seed whatever truly survived (the title-snapshot precedent,
+   * generalized).
+   * @param lastSeq - the subscribed frame's durable baseline seq.
+   */
+  truncate(lastSeq: number): void {
+    for (const [key, row] of this.rows) {
+      if (row.seq <= lastSeq) continue
+      this.rows.delete(key)
+      this.changed(key)
+    }
+  }
+
+  private changed(key: string): void {
+    this.channels.get(key)?.notifier.markDirty()
+    this.anyNotifier.markDirty()
+  }
+
+  private channel(key: string): Channel {
+    let channel = this.channels.get(key)
+    if (channel === undefined) {
+      // The notifier only batches (no snapshot cache to rebuild: faces read rows directly).
+      const notifier = new Notifier(() => {})
+      channel = {
+        notifier,
+        face: {
+          getSnapshot: () => this.rows.get(key)?.value,
+          subscribe: listener => notifier.subscribe(listener),
+        },
+      }
+      this.channels.set(key, channel)
+    }
+    return channel
+  }
+}
--- a/packages/client/runtime/src/client/sessions/service.ts
+++ b/packages/client/runtime/src/client/sessions/service.ts
@@ -301,7 +301,7 @@ export class SessionsService {
        props[name] = undefined
      }
    }
-    return { sessionId: undefined, hooks, props }
+    return { sessionId: undefined, hooks, props } // no projections face: every key reads absent without a session
  }

  /** Materialize the standard-props bundle for one session (fails loud on duplicate member names). */
@@ -334,7 +334,14 @@ export class SessionsService {
        props[name] = contributedProps[name]
      }
    }
-    return { sessionId: binding.sessionId, hooks, props }
+    return {
+      sessionId: binding.sessionId,
+      hooks,
+      props,
+      // The useProjection seat: key-addressed bare value faces off the
+      // session's projection store (open key space — never a static roster member).
+      projections: { faceOf: key => binding.session.projections.faceOf(key) },
+    }
  }

  /**
--- a/packages/client/runtime/src/client/sessions/session.ts
+++ b/packages/client/runtime/src/client/sessions/session.ts
@@ -2,7 +2,7 @@

 import type { Context } from 'cordis'
 import type { ContentBlock } from '@deepseek-ai/dsh-llm/types'
-import type { SessionEvent, TodoItem } from '@deepseek-ai/dsh-session/types'
+import type { SessionEvent } from '@deepseek-ai/dsh-session/types'
 import type {
  HistoryEntry, IApiClient, MuxFrame, RpcError, RpcId, RpcResult,
  SessionId, ToolEventView,
@@ -23,6 +23,8 @@ import { PendingWait } from './pending.ts'
 import { FoldAdapter } from './fold-adapter.ts'
 import { Notifier } from './notifier.ts'
 import { PartialAccumulator } from './partial.ts'
+import { ProjectionValueStore } from './projection-store.ts'
+import type { ProjectionsBaseline } from './projection-store.ts'

 /** Messages requested per history page. */
 export const PAGE_MESSAGES = 50
@@ -38,6 +40,12 @@ export interface SessionOptions {
   * (hidden, still reusable by connectWorkspace).
   */
  onEngaged?(session: Session): void
+  /**
+   * Manager-owned projection value store to adopt (frames route through the
+   * manager and values outlive instantiation); omitted, the Session owns a
+   * private store (bare object-layer construction).
+   */
+  projections?: ProjectionValueStore
 }

 /** Queue-row preview cap: the dock renders one line, the full content never leaves the host mirror. */
@@ -103,9 +111,6 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
  private queueCache: { rev: number; value: QueuedMessage[] } | null = null
  private frozenRev = 0
  private nodesCache: { folded: readonly ConversationNode[]; frozenRev: number; value: readonly ConversationNode[] } | null = null
-  /** Current whole-list todo/write projection: each tail history response replaces it (an omitted
-   *  field is the authoritative empty list) and every live write overwrites it. */
-  private todos: readonly TodoItem[] = []
  /** `run_code` sub-dispatches by parent callId (window-derived, like openCalls). Appends
   *  copy-on-write the per-parent array so published snapshot references never mutate. */
  private codeDispatches = new Map<string, readonly CodeSubCall[]>()
@@ -137,6 +142,19 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
  /** subscribed.lastSeq baseline (gap detection; null when no subscribed frame arrived — degrade to the liveBuffer dedup path). */
  private subscribedLastSeq: number | null = null

+  /**
+   * Per-session projection value store (session-projection RFC, push model):
+   * finished whole values computed on the host, seeded by the tail page's
+   * projections block and updated by `session/projection` frames under the
+   * one higher-seq-wins rule. Keys are read via `projections.faceOf(key)`
+   * (the useProjection resolution face); the conversation snapshot never
+   * carries projection values, and no client-side domain folding exists.
+   * Manager-owned when constructed through SessionManager (frames route and
+   * the store outlives instantiation, the title-snapshot precedent); a bare
+   * construction gets a private store.
+   */
+  readonly projections: ProjectionValueStore
+
  private snapshotCache: ConversationSnapshot
  private readonly notifier = new Notifier(() => {
    this.snapshotCache = this.buildSnapshot()
@@ -160,6 +178,7 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
    private readonly api: IApiClient,
    private readonly options: SessionOptions = {},
  ) {
+    this.projections = options.projections ?? new ProjectionValueStore()
    this.snapshotCache = this.buildSnapshot()
  }

@@ -523,13 +542,13 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
        this.openError = result.error
        return
      }
-      this.installWindow(result.value.events, result.value.hasMore, result.value.todos)
+      this.installWindow(result.value.events, result.value.hasMore, result.value.projections)
      // Gap detection (§D.3-4): baseline past the window tail and liveBuffer did not cover it -> pull the tail page once more.
      const tailSeq = this.windowTailSeq()
      if (this.subscribedLastSeq !== null && tailSeq !== null && this.subscribedLastSeq > tailSeq) {
        result = (await this.api.sessions.history({ sessionId: this.sessionId, maxMessages: PAGE_MESSAGES })).result
        if (generation !== this.openGeneration) return
-        if (result.ok) this.installWindow(result.value.events, result.value.hasMore, result.value.todos)
+        if (result.ok) this.installWindow(result.value.events, result.value.hasMore, result.value.projections)
      }
      this.openState = 'open'
    } catch (error) {
@@ -546,23 +565,19 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
  /** Install the history window + stitch the liveBuffer (seq is the sole dedup key).
   *  Stitching MUST NOT route through acceptLiveEvent: openState is still 'loading' here
   *  (doOpen flips it after install), so recursing would push every buffered event straight
-   *  back into liveBuffer where nothing ever drains it — a silent drop loop (audit S1). */
-  private installWindow(entries: HistoryEntry[], hasMore: boolean, todos: readonly TodoItem[] | undefined): void {
+   *  back into liveBuffer where nothing ever drains it — a silent drop loop (audit S1).
+   *  A carried projections block seeds the value store (higher seq wins, so a stale
+   *  baseline cannot overwrite a newer push frame); the window events themselves are
+   *  never folded — the host is the only computation site. */
+  private installWindow(entries: HistoryEntry[], hasMore: boolean, projections?: ProjectionsBaseline): void {
    this.events = entries.map(e => e.event)
    this.views = entries.map(e => e.view)
    this.historyRev++
    this.baseSeq = this.events[0]?.seq ?? 0
    this.hasMore = hasMore
-    // Session-level projection from the tail page (full-log latest todo/write,
-    // independent of the window); an in-window write below re-derives the same
-    // value, and later live events keep overwriting it. Every caller here is a
-    // tail request (no beforeSeq), which the host answers with the projection
-    // or omits it only when the full log holds no todo/write — so an absent
-    // field is the authoritative empty list, not a missing carrier. Assigning
-    // it clears a plan the log never kept (a write lost to a host crash).
-    this.todos = todos ?? []
    this.foldAdapter.reset(this.events, this.baseSeq, this.views)
    this.rebuildDerivedFromWindow()
+    if (projections !== undefined) this.projections.seed(projections)
    const buffered = this.liveBuffer
    this.liveBuffer = []
    for (const item of buffered) this.appendLive(item.event, item.view)
@@ -612,7 +627,7 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
      const { result } = await this.api.sessions.history({ sessionId: this.sessionId, maxMessages: PAGE_MESSAGES })
      // Failure or superseded by a full resync: drop — the resync path rebuilds and clears the buffer itself.
      if (result.ok && generation === this.openGeneration && this.openState === 'open') {
-        this.installWindow(result.value.events, result.value.hasMore, result.value.todos)
+        this.installWindow(result.value.events, result.value.hasMore, result.value.projections)
      }
    } catch (error) {
      console.error('[web-runtime] gap repair failed:', error)
@@ -732,10 +747,6 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
        if (this.openCalls.delete(String(event.data.callId))) this.callsRev++
        return
      }
-      case 'todo/write': {
-        this.todos = event.data.todos
-        return
-      }
      case 'turn/end': {
        // Aborted turns never finalize. The accumulated partial is VALUE, not residue: freeze it
        // into an interrupted terminal node (pulse stops, text survives) instead of deleting it.
@@ -780,10 +791,7 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {

  /** Re-derive state (partial/openCalls/frozenNodes) from raw window events after a rebuild — keeps
   *  paging/stitching consistent, and makes the live freeze and the history replay converge on the
-   *  same interrupted nodes (chunks are logged, so the replayed sweep re-freezes identical text).
-   *  todos is deliberately NOT reset: it is session-level (seeded by the tail page's full-log
-   *  projection, not derivable from an arbitrary window). The window always extends to the log
-   *  tail, so an in-window todo/write can only overwrite it with the same latest value. */
+   *  same interrupted nodes (chunks are logged, so the replayed sweep re-freezes identical text). */
  private rebuildDerivedFromWindow(): void {
    this.partial = null
    this.openCalls.clear()
@@ -854,7 +862,6 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
      promptError: this.promptError,
      blank: this.blankBit,
      lastAgentError: this.lastAgentError,
-      todos: this.todos,
    }
  }

--- a/packages/client/runtime/src/client/workspaces/service.ts
+++ b/packages/client/runtime/src/client/workspaces/service.ts
@@ -182,6 +182,17 @@ export class WorkspacesService {
    return response.result.value.path
  }

+  /**
+   * Open a filesystem path with the Host operating system's default application.
+   * @param path - absolute or host-resolvable path.
+   */
+  async openPath(path: string): Promise<void> {
+    const response = await this.api.host.openPath({ path })
+    if (!response.result.ok) {
+      throw new Error(`path open failed: ${response.result.error.message}`)
+    }
+  }
+
  /**
   * Rename a Workspace.
   * @param workspaceId - target workspace.
--- a/packages/client/runtime/tests/event-script.ts
+++ b/packages/client/runtime/tests/event-script.ts
@@ -40,8 +40,10 @@ export const ev = {
    at(seq, { type: 'step/end', data: { turn, step } }),
  turnEnd: (seq: number, turn: number, reason: 'completed' | 'cancelled' = 'completed'): SessionEvent =>
    at(seq, { type: 'turn/end', data: { turn, reason: { kind: reason } } }),
-  todoWrite: (seq: number, todos: { content: string; status: 'pending' | 'in_progress' | 'completed' }[]): SessionEvent =>
-    at(seq, { type: 'todo/write', data: { todos } }),
+  commandRun: (seq: number, commandId: string, name: string, args = ''): SessionEvent =>
+    at(seq, { type: 'command/run', data: { commandId, name, args, source: { kind: 'user' } } }),
+  commandDone: (seq: number, commandId: string, kind: 'success' | 'error' = 'success', text?: string): SessionEvent =>
+    at(seq, { type: 'command/done', data: { commandId, kind, ...text === undefined ? {} : { text } } }),
 }

 /** One complete plain turn (turn/start → user → step → assistant → turn/end), 6 events from startSeq. */
--- a/packages/client/runtime/tests/fake-api.ts
+++ b/packages/client/runtime/tests/fake-api.ts
@@ -1,8 +1,9 @@
 // Test-local programmable IApiClient fake (NOT the fixture: fixture is a demo
 // data source on a real clock; behavior tests need per-case responses and
 // deferred-controlled timing). Streams are hand pumps: pushMux/pushHost.
+import type { CommandId } from '@deepseek-ai/dsh-commands/brand'
 import type {
-  ClientResponse, CommandDescriptor, CommandExecuteResult, HostFrame, IApiClient, ModelTarget, MuxFrame,
+  ClientResponse, CommandDescriptor, HostFrame, IApiClient, ModelTarget, MuxFrame,
  RpcError, RpcReceipt, RpcRequest, RpcResponse, SessionId, SessionModels, SkillEntry,
  WorkspaceId, WorkspaceView,
 } from '@deepseek-ai/dsh-client-connection/client'
@@ -63,7 +64,7 @@ export class FakeApiClient implements IApiClient {
  onCreate: (payload: unknown) => Promise<RpcResponse<{ sessionId: SessionId }>> = () => Promise.resolve(ok({ sessionId: 'fk-new' as SessionId }))
  readonly defaultModel: ModelTarget = { provider: 'deepseek', model: 'deepseek-v4-flash' }
  onHistory: (payload: { sessionId: SessionId; beforeSeq?: number; maxMessages?: number })
-  => Promise<RpcResponse<{ events: never[]; hasMore: boolean; todos?: { content: string; status: 'pending' | 'in_progress' | 'completed' }[] }>> =
+  => Promise<RpcResponse<{ events: never[]; hasMore: boolean }>> =
    () => Promise.resolve(ok({ events: [], hasMore: false }))

  onModels: (payload: unknown) => Promise<RpcResponse<SessionModels>> = () => Promise.resolve(ok({
@@ -84,6 +85,8 @@ export class FakeApiClient implements IApiClient {
    () => Promise.resolve(ok({ version: '0-fake', cwd: '/f', attachedSessions: 0 }))
  onPickDirectory: (payload: unknown) => Promise<RpcResponse<{ path: string | null }>> =
    () => Promise.resolve(ok({ path: null }))
+  onOpenPath: (payload: unknown) => Promise<RpcResponse<{ opened: true }>> =
+    () => Promise.resolve(ok({ opened: true as const }))

  private readonly muxConns: StreamConn<MuxFrame>[] = []
  private readonly hostConns: StreamConn<HostFrame>[] = []
@@ -106,6 +109,7 @@ export class FakeApiClient implements IApiClient {
  readonly host: IApiClient['host'] = {
    describe: (payload: unknown) => this.record('host.describe', payload, this.onDescribe(payload)),
    pickDirectory: (payload: unknown) => this.record('host.pickDirectory', payload, this.onPickDirectory(payload)),
+    openPath: (payload: unknown) => this.record('host.openPath', payload, this.onOpenPath(payload)),
  }

  onWorkspaceList: (payload: unknown) => Promise<RpcResponse<{ items: never[] }>> = () => Promise.resolve(ok({ items: [] }))
@@ -133,10 +137,12 @@ export class FakeApiClient implements IApiClient {
  // Payloads stay `unknown` (lint-lane note above); response rows are the real
  // wire shapes so cases can program requires-bearing catalogs and dual-address
  // skill lists without casts.
-  onCommandList: (payload: unknown) => Promise<RpcResponse<{ commands: CommandDescriptor[] }>> = () => Promise.resolve(ok({ commands: [] }))
-  onCommandExecute: (payload: unknown) => Promise<RpcResponse<{ matched: boolean; result?: CommandExecuteResult }>> =
-    () => Promise.resolve(ok({ matched: false }))
-  onSkillList: (payload: unknown) => Promise<RpcResponse<{ skills: SkillEntry[] }>> = () => Promise.resolve(ok({ skills: [] }))
+  onCommandList: (payload: unknown) => Promise<RpcResponse<{ commands: CommandDescriptor[] }>>
+    = () => Promise.resolve(ok({ commands: [] }))
+  onCommandExecute: (payload: unknown) => Promise<RpcResponse<{ matched: boolean; commandId?: CommandId }>>
+    = () => Promise.resolve(ok({ matched: false }))
+  onSkillList: (payload: unknown) => Promise<RpcResponse<{ skills: SkillEntry[] }>>
+    = () => Promise.resolve(ok({ skills: [] }))

  readonly commands: IApiClient['commands'] = {
    list: (payload: unknown) => this.record('command.list', payload, this.onCommandList(payload)),
--- a/packages/client/runtime/tests/fold-adapter.spec.ts
+++ b/packages/client/runtime/tests/fold-adapter.spec.ts
@@ -184,4 +184,75 @@ describe('FoldAdapter', () => {
    const node = adapter.nodes().nodes[0]
    expect(node).toMatchObject({ kind: 'tool-result', call: null, callView: null, resultView: { title: '孤儿' } })
  })
+
+  describe('command lifecycle nodes', () => {
+    it('folds a run/done pair into one settled node merged into flow order by seq', () => {
+      const adapter = new FoldAdapter()
+      adapter.reset([
+        ev.user(0, '先说话'),
+        ev.commandRun(1, 'cmd-1', 'plan'),
+        ev.commandDone(2, 'cmd-1', 'success', '已进入 plan mode'),
+        ev.assistant(3, 0, '然后回答'),
+      ], 0)
+      const { nodes } = adapter.nodes()
+      expect(nodes.map(n => [n.kind, n.seq])).toEqual([['user', 0], ['command', 1], ['assistant', 3]])
+      expect(nodes[1]).toMatchObject({
+        kind: 'command', commandId: 'cmd-1', name: 'plan', args: '',
+        outcome: { kind: 'success', text: '已进入 plan mode' },
+      })
+    })
+
+    it('renders a run with no done as still executing (outcome null)', () => {
+      const adapter = new FoldAdapter()
+      adapter.reset([ev.commandRun(0, 'cmd-2', 'goal', ' ship it')], 0)
+      expect(adapter.nodes().nodes[0]).toMatchObject({
+        kind: 'command', name: 'goal', args: ' ship it', outcome: null,
+      })
+    })
+
+    it('soft-falls a done-only window into a node built from the done (cross-window cut)', () => {
+      const adapter = new FoldAdapter()
+      adapter.reset([ev.commandDone(80, 'cmd-3', 'error', '失败了')], 80)
+      expect(adapter.nodes().nodes[0]).toMatchObject({
+        kind: 'command', seq: 80, commandId: 'cmd-3', name: null, args: null,
+        outcome: { kind: 'error', text: '失败了' },
+      })
+    })
+
+    it('settles a live-appended done in place, keeping the node at the run seq', () => {
+      const adapter = new FoldAdapter()
+      adapter.reset(plainTurn(0, 0, 'q', 'a'), 0)
+      adapter.append(ev.commandRun(6, 'cmd-4', 'clear'))
+      const running = adapter.nodes().nodes.find(n => n.kind === 'command')
+      expect(running).toMatchObject({ outcome: null })
+      adapter.append(ev.commandDone(7, 'cmd-4'))
+      const settled = adapter.nodes().nodes.find(n => n.kind === 'command')
+      expect(settled).toMatchObject({ seq: 6, outcome: { kind: 'success' } })
+      // Settlement replaced the node object rather than mutating the published one.
+      expect(settled).not.toBe(running)
+    })
+
+    it('tails command nodes whose seq is past every surface node', () => {
+      const adapter = new FoldAdapter()
+      adapter.reset([ev.user(0, '问'), ev.commandRun(1, 'cmd-tail', 'plan')], 0)
+      expect(adapter.nodes().nodes.map(n => n.kind)).toEqual(['user', 'command'])
+    })
+
+    it('command nodes survive the degraded linear-scan branch', () => {
+      const adapter = new FoldAdapter()
+      const errorSpy = vi.spyOn(console, 'error').mockImplementation(() => undefined)
+      try {
+        adapter.reset([
+          ev.commandRun(0, 'cmd-5', 'plan'),
+          ev.commandDone(1, 'cmd-5'),
+          at(2, { type: 'assistant/message', surfaceOp: 'bogus-op', data: { turn: 0, step: 0, content: [{ type: 'text', text: '坏 op' }], provenance: { provider: 'x', model: 'y' } } }),
+        ], 0)
+        const { nodes, degraded } = adapter.nodes()
+        expect(degraded).toBe(true)
+        expect(nodes.some(n => n.kind === 'command')).toBe(true)
+      } finally {
+        errorSpy.mockRestore()
+      }
+    })
+  })
 })
--- a/packages/client/runtime/tests/manager.spec.ts
+++ b/packages/client/runtime/tests/manager.spec.ts
@@ -133,21 +133,18 @@ describe('list lifecycle', () => {
    expect(manager.getListSnapshot().items.map(i => i.sessionId)).toEqual([S2])
  })

-  it('retains monotonic title snapshots before list arrival, merges recency, and clears them on removal', async () => {
+  it('retains title projections before list arrival, keeps last-wins by seq, and clears them on removal', async () => {
    const api = new FakeApiClient()
    const manager = new SessionManager(api)
-    manager.handleMuxEnvelope({
-      rpcId: 'title-new' as never,
-      payload: { type: 'session/title', sessionId: S1, title: 'Newest', eventSeq: 4, updatedAt: 300 },
-    })
-    manager.handleMuxEnvelope({
-      rpcId: 'title-stale' as never,
-      payload: { type: 'session/title', sessionId: S1, title: 'Stale', eventSeq: 3, updatedAt: 900 },
-    })
-    manager.handleMuxEnvelope({
-      rpcId: 'title-equal' as never,
-      payload: { type: 'session/title', sessionId: S1, title: 'Equal', eventSeq: 4, updatedAt: 901 },
-    })
+    const titleFrame = (rpcId: string, title: string, seq: number) => {
+      manager.handleMuxEnvelope({
+        rpcId: rpcId as never,
+        payload: { type: 'session/projection', sessionId: S1, key: 'title', value: title, seq } as never,
+      })
+    }
+    titleFrame('title-new', 'Newest', 4)
+    titleFrame('title-stale', 'Stale', 3)
+    titleFrame('title-equal', 'Equal', 4)
    api.onList = () => Promise.resolve(ok({
      items: [summary(S1), summary(S2, { updatedAt: 200 })] as never[],
    }))
@@ -155,7 +152,7 @@ describe('list lifecycle', () => {

    const titled = manager.getListSnapshot()
    expect(titled.items.map(item => item.sessionId)).toEqual([S1, S2])
-    expect(titled.items[0]).toMatchObject({ title: 'Newest', updatedAt: 300 })
+    expect(titled.items[0]?.title).toBe('Newest')
    expect(titled.items[1]?.title).toBeUndefined()

    manager.handleHostEnvelope({ rpcId: 'removed' as never, payload: { type: 'host/session-removed', sessionId: S1 } })
@@ -163,34 +160,27 @@ describe('list lifecycle', () => {
    expect(manager.getListSnapshot().items.find(item => item.sessionId === S1)?.title).toBeUndefined()
  })

-  it('drops a retained title beyond the subscription baseline before accepting its durable replay', async () => {
+  it('drops a projection row beyond the subscription baseline before accepting its durable replay', async () => {
    const api = new FakeApiClient()
    api.onList = () => Promise.resolve(ok({ items: [summary(S1)] as never[] }))
    const manager = new SessionManager(api)
    await manager.refreshList()
-    manager.handleMuxEnvelope({
-      rpcId: 'title-unflushed' as never,
-      payload: { type: 'session/title', sessionId: S1, title: 'Unflushed', eventSeq: 4, updatedAt: 400 },
-    })
+    const frame = (rpcId: string, payload: object) => {
+      manager.handleMuxEnvelope({ rpcId: rpcId as never, payload: payload as never })
+    }
+    frame('title-unflushed', { type: 'session/projection', sessionId: S1, key: 'title', value: 'Unflushed', seq: 4 })

-    manager.handleMuxEnvelope({
-      rpcId: 'subscribed-recovered' as never,
-      payload: { type: 'session/subscribed', sessionId: S1, lastSeq: 2 },
-    })
+    // The durable baseline says the host only knows up to seq 2: the phantom
+    // row rode lost state and must drop, or last-wins pins it forever.
+    frame('subscribed-recovered', { type: 'session/subscribed', sessionId: S1, lastSeq: 2 })
    expect(manager.getListSnapshot().items[0]?.title).toBeUndefined()
-    expect(manager.getListSnapshot().items[0]?.updatedAt).toBe(100)

-    manager.handleMuxEnvelope({
-      rpcId: 'title-durable' as never,
-      payload: { type: 'session/title', sessionId: S1, title: 'Durable', eventSeq: 2, updatedAt: 200 },
-    })
-    expect(manager.getListSnapshot().items[0]).toMatchObject({ title: 'Durable', updatedAt: 200 })
+    frame('title-durable', { type: 'session/projection', sessionId: S1, key: 'title', value: 'Durable', seq: 2 })
+    expect(manager.getListSnapshot().items[0]?.title).toBe('Durable')

-    manager.handleMuxEnvelope({
-      rpcId: 'subscribed-current' as never,
-      payload: { type: 'session/subscribed', sessionId: S1, lastSeq: 2 },
-    })
-    expect(manager.getListSnapshot().items[0]).toMatchObject({ title: 'Durable', updatedAt: 200 })
+    // A baseline at or past the row's seq keeps it (nothing phantom to drop).
+    frame('subscribed-current', { type: 'session/subscribed', sessionId: S1, lastSeq: 2 })
+    expect(manager.getListSnapshot().items[0]?.title).toBe('Durable')
  })
 })

--- a/packages/client/runtime/tests/projection-store.spec.ts
+++ b/packages/client/runtime/tests/projection-store.spec.ts
@@ -0,0 +1,187 @@
+/**
+ * Projection value store (session-projection RFC, push model): the single
+ * higher-seq-wins rule on both paths (a stale baseline cannot overwrite a
+ * newer push frame; a replayed frame cannot regress), capability absence as
+ * undefined, generation truncation, and the Session/manager wiring (tail-page
+ * seeding, session/projection frame routing pre- and post-instantiation, the
+ * list rows' title projection).
+ */
+import { describe, expect, it } from 'vitest'
+import type { SessionId } from '@deepseek-ai/dsh-client-connection/client'
+import { ProjectionValueStore } from '../src/client/sessions/projection-store.ts'
+import { Session } from '../src/client/sessions/session.ts'
+import { SessionManager } from '../src/client/sessions/manager.ts'
+import { FakeApiClient, ok } from './fake-api.ts'
+import { entries, plainTurn } from './event-script.ts'
+
+// Test-domain keys merged into the projection map (the interface package's
+// pure-type outlet), the same way domain host plugins merge theirs.
+declare module '@deepseek-ai/dsh-session-projection/types' {
+  interface SessionProjectionMap {
+    'test/marks': { marks: string[] }
+  }
+}
+
+const SID = 'fk-s1' as SessionId
+
+describe('ProjectionValueStore semantics', () => {
+  it('reads undefined until a value lands (capability absence)', () => {
+    const store = new ProjectionValueStore()
+    expect(store.get('test/marks')).toBeUndefined()
+    expect(store.faceOf('test/marks').getSnapshot()).toBeUndefined()
+  })
+
+  it('applies frames last-wins by seq: replayed and stale frames drop', () => {
+    const store = new ProjectionValueStore()
+    store.apply('test/marks', { marks: ['a'] }, 5)
+    store.apply('test/marks', { marks: ['a', 'b'] }, 9)
+    expect(store.get('test/marks')).toEqual({ marks: ['a', 'b'] })
+    store.apply('test/marks', { marks: ['stale'] }, 5)
+    store.apply('test/marks', { marks: ['equal'] }, 9)
+    expect(store.get('test/marks')).toEqual({ marks: ['a', 'b'] })
+  })
+
+  it('a stale baseline can neither overwrite nor clear a newer frame; a fresh one reseeds and clears', () => {
+    const store = new ProjectionValueStore()
+    store.apply('test/marks', { marks: ['frame-20'] }, 20)
+    // Stale cut: carried key loses to the newer frame; omitted key survives.
+    store.seed({ asOfSeq: 10, values: { 'test/marks': { marks: ['baseline-10'] } } })
+    expect(store.get('test/marks')).toEqual({ marks: ['frame-20'] })
+    store.seed({ asOfSeq: 15, values: {} })
+    expect(store.get('test/marks')).toEqual({ marks: ['frame-20'] })
+    // Fresh cut: carried key reseeds…
+    store.seed({ asOfSeq: 30, values: { 'test/marks': { marks: ['baseline-30'] } } })
+    expect(store.get('test/marks')).toEqual({ marks: ['baseline-30'] })
+    // …and an omitting fresh cut clears (capability absent as of the cut).
+    store.seed({ asOfSeq: 40, values: {} })
+    expect(store.get('test/marks')).toBeUndefined()
+  })
+
+  it('truncate drops rows past the durable baseline and keeps the rest', () => {
+    const store = new ProjectionValueStore()
+    store.apply('test/marks', { marks: ['durable'] }, 5)
+    store.apply('other', 'phantom', 50)
+    store.truncate(10)
+    expect(store.get('test/marks')).toEqual({ marks: ['durable'] })
+    expect(store.get('other')).toBeUndefined()
+  })
+
+  it('notifies the key face on change (batched) and not on dropped applications', async () => {
+    const store = new ProjectionValueStore()
+    let keyTicks = 0
+    let anyTicks = 0
+    store.faceOf('test/marks').subscribe(() => { keyTicks += 1 })
+    store.subscribeAny(() => { anyTicks += 1 })
+    store.apply('test/marks', { marks: ['a'] }, 5)
+    await Promise.resolve()
+    expect(keyTicks).toBe(1)
+    expect(anyTicks).toBe(1)
+    store.apply('test/marks', { marks: ['replay'] }, 3)
+    await Promise.resolve()
+    expect(keyTicks).toBe(1)
+    expect(anyTicks).toBe(1)
+  })
+
+  it('faces are identity-stable per key (the React binding cache premise)', () => {
+    const store = new ProjectionValueStore()
+    expect(store.faceOf('test/marks')).toBe(store.faceOf('test/marks'))
+  })
+})
+
+describe('Session tail-page seeding', () => {
+  it('seeds the store from a history response carrying a projections block', async () => {
+    const api = new FakeApiClient()
+    const session = new Session(SID, api)
+    api.onHistory = () => Promise.resolve(ok({
+      events: entries(plainTurn(0, 0, '问', '答')) as never[], hasMore: false,
+      projections: { asOfSeq: 5, values: { 'test/marks': { marks: ['from-baseline'] } } },
+    } as never))
+    await session.open()
+    expect(session.projections.get('test/marks')).toEqual({ marks: ['from-baseline'] })
+  })
+
+  it('a resync serving a stale block keeps the newer pushed value (seq rule end to end)', async () => {
+    const api = new FakeApiClient()
+    const session = new Session(SID, api)
+    api.onHistory = () => Promise.resolve(ok({
+      events: entries(plainTurn(0, 0, 'a', 'b')) as never[], hasMore: false,
+      projections: { asOfSeq: 5, values: { 'test/marks': { marks: ['baseline'] } } },
+    } as never))
+    await session.open()
+    session.projections.apply('test/marks', { marks: ['pushed-9'] }, 9)
+    await session.resync()
+    expect(session.projections.get('test/marks')).toEqual({ marks: ['pushed-9'] })
+  })
+
+  it('treats a blockless response as no reset: pushed values survive', async () => {
+    const api = new FakeApiClient()
+    const session = new Session(SID, api)
+    api.onHistory = () => Promise.resolve(ok({ events: entries(plainTurn(0, 0, 'a', 'b')) as never[], hasMore: false }))
+    await session.open()
+    session.projections.apply('test/marks', { marks: ['pushed'] }, 9)
+    await session.resync()
+    expect(session.projections.get('test/marks')).toEqual({ marks: ['pushed'] })
+  })
+})
+
+describe('manager frame routing', () => {
+  const sid = (s: string): SessionId => s as SessionId
+
+  it('lands session/projection frames before instantiation and the Session adopts the same store', async () => {
+    const api = new FakeApiClient()
+    const manager = new SessionManager(api)
+    manager.handleMuxEnvelope({
+      rpcId: 'p1' as never,
+      payload: { type: 'session/projection', sessionId: sid('s1'), key: 'test/marks', value: { marks: ['early'] }, seq: 7 } as never,
+    })
+    const session = manager.get(sid('s1'))
+    expect(session.projections.get('test/marks')).toEqual({ marks: ['early'] })
+    // Frames after instantiation land in the same store.
+    manager.handleMuxEnvelope({
+      rpcId: 'p2' as never,
+      payload: { type: 'session/projection', sessionId: sid('s1'), key: 'test/marks', value: { marks: ['later'] }, seq: 9 } as never,
+    })
+    expect(session.projections.get('test/marks')).toEqual({ marks: ['later'] })
+  })
+
+  it('projects the title key into list rows and truncates phantom rows on the subscribed baseline', async () => {
+    const api = new FakeApiClient()
+    const manager = new SessionManager(api)
+    api.onList = () => Promise.resolve(ok({
+      items: [{ sessionId: sid('s1'), updatedAt: 1, running: false, blank: false }],
+    }) as never)
+    await manager.refreshList()
+    manager.handleMuxEnvelope({
+      rpcId: 't1' as never,
+      payload: { type: 'session/projection', sessionId: sid('s1'), key: 'title', value: 'Projected title', seq: 4 } as never,
+    })
+    await Promise.resolve()
+    expect(manager.getListSnapshot().items[0]?.title).toBe('Projected title')
+    // The durable baseline says the host only knows up to seq 2: the row rode
+    // lost state and must drop (the un-flushed title precedent).
+    manager.handleMuxEnvelope({
+      rpcId: 'sub' as never,
+      payload: { type: 'session/subscribed', sessionId: sid('s1'), lastSeq: 2 } as never,
+    })
+    await Promise.resolve()
+    expect(manager.getListSnapshot().items[0]?.title).toBeUndefined()
+  })
+
+  it('drops the projection store with the removed session', async () => {
+    const api = new FakeApiClient()
+    const manager = new SessionManager(api)
+    api.onList = () => Promise.resolve(ok({
+      items: [{ sessionId: sid('s1'), updatedAt: 1, running: false, blank: false }],
+    }) as never)
+    await manager.refreshList()
+    manager.handleMuxEnvelope({
+      rpcId: 't1' as never,
+      payload: { type: 'session/projection', sessionId: sid('s1'), key: 'title', value: 'Doomed', seq: 4 } as never,
+    })
+    manager.handleHostEnvelope({
+      rpcId: 'rm' as never,
+      payload: { type: 'host/session-removed', sessionId: sid('s1') } as never,
+    })
+    expect(manager.get(sid('s1')).projections.get('title')).toBeUndefined()
+  })
+})
--- a/packages/client/runtime/tests/session.spec.ts
+++ b/packages/client/runtime/tests/session.spec.ts
@@ -22,9 +22,9 @@ function makeSession(api = new FakeApiClient()): { api: FakeApiClient; session:
  return { api, session: new Session(SID, api) }
 }

-function histResponse(events: SessionEvent[], hasMore = false, todos?: { content: string; status: 'pending' | 'in_progress' | 'completed' }[]) {
+function histResponse(events: SessionEvent[], hasMore = false) {
  // history now returns HistoryEntry[] ({event, view?}); these tests are view-less.
-  return Promise.resolve(ok({ events: entries(events) as never[], hasMore, ...todos === undefined ? {} : { todos } }))
+  return Promise.resolve(ok({ events: entries(events) as never[], hasMore }))
 }

 describe('open', () => {
@@ -104,6 +104,28 @@ describe('live event path', () => {
    expect(session.getSnapshot().nodes).toEqual(before.nodes)
  })

+  it('materializes a command node from live lifecycle frames and reproduces it from a history window', async () => {
+    // Live path: run mints an executing node, done settles it in the flow.
+    const { session } = await opened()
+    const feed = (event: SessionEvent) => { session.handleMuxEnvelope('r' as never, { type: 'session/event', sessionId: SID, event }) }
+    feed(ev.commandRun(6, 'cmd-live', 'plan'))
+    let command = session.getSnapshot().nodes.at(-1)
+    expect(command).toMatchObject({ kind: 'command', name: 'plan', args: '', outcome: null })
+    feed(ev.commandDone(7, 'cmd-live', 'success', '已进入 plan mode'))
+    command = session.getSnapshot().nodes.at(-1)
+    expect(command).toMatchObject({ kind: 'command', seq: 6, outcome: { kind: 'success', text: '已进入 plan mode' } })
+
+    // Replay path (refresh): the same pair inside the history window folds identically.
+    const replayed = await opened([
+      ...plainTurn(0, 0, 'a', 'b'),
+      ev.commandRun(6, 'cmd-live', 'plan'),
+      ev.commandDone(7, 'cmd-live', 'success', '已进入 plan mode'),
+    ])
+    expect(replayed.session.getSnapshot().nodes.at(-1)).toMatchObject({
+      kind: 'command', seq: 6, name: 'plan', outcome: { kind: 'success', text: '已进入 plan mode' },
+    })
+  })
+
  it('accumulates chunks into partial, then finalize swaps partial out as the node lands', async () => {
    const { session } = await opened()
    const feed = (event: SessionEvent) => { session.handleMuxEnvelope('r' as never, { type: 'session/event', sessionId: SID, event }) }
@@ -173,42 +195,6 @@ describe('live event path', () => {
    })
  })

-  it('folds todo/write into snapshot.todos last-write-wins, live and on window replay', async () => {
-    const listA = [{ content: '搭骨架', status: 'completed' as const }, { content: '写组件', status: 'in_progress' as const }]
-    const listB = [{ content: '搭骨架', status: 'completed' as const }, { content: '写组件', status: 'completed' as const }]
-    const { session } = await opened()
-    expect(session.getSnapshot().todos).toEqual([])
-    const feed = (event: SessionEvent) => { session.handleMuxEnvelope('r' as never, { type: 'session/event', sessionId: SID, event }) }
-    feed(ev.todoWrite(6, listA))
-    expect(session.getSnapshot().todos).toEqual(listA)
-    feed(ev.todoWrite(7, listB))
-    expect(session.getSnapshot().todos).toEqual(listB)
-    // Window replay converges on the same last snapshot (history contains both writes).
-    const replayed = makeSession()
-    replayed.api.onHistory = () => histResponse([...plainTurn(0, 0, 'a', 'b'), ev.todoWrite(6, listA), ev.todoWrite(7, listB)])
-    await replayed.session.open()
-    expect(replayed.session.getSnapshot().todos).toEqual(listB)
-  })
-
-  it('seeds todos from the tail page projection when the last write precedes the window', async () => {
-    const list = [{ content: '窗口外的计划', status: 'in_progress' as const }]
-    // Cold open: the page window carries NO todo/write; the projection rides the response.
-    const { api, session } = makeSession()
-    api.onHistory = () => histResponse(plainTurn(100, 9, '问', '答'), true, list)
-    await session.open()
-    expect(session.getSnapshot().todos).toEqual(list)
-    // Paging an older window in must not clear the session-level projection.
-    api.onHistory = () => histResponse(plainTurn(94, 8, '旧问', '旧答'), false)
-    await session.loadOlder()
-    expect(session.getSnapshot().todos).toEqual(list)
-    // A later live write still overrides the seeded projection.
-    session.handleMuxEnvelope('r' as never, {
-      type: 'session/event', sessionId: SID,
-      event: ev.todoWrite(106, [{ content: '新计划', status: 'pending' as const }]),
-    })
-    expect(session.getSnapshot().todos).toEqual([{ content: '新计划', status: 'pending' }])
-  })
-
  it('repairs a seq gap by repulling the tail page instead of appending a hole', async () => {
    const { api, session } = await opened(plainTurn(0, 0, 'a', 'b')) // tail seq = 5
    const repaired = [...plainTurn(0, 0, 'a', 'b'), ...plainTurn(6, 1, 'c', 'd')]
@@ -222,37 +208,6 @@ describe('live event path', () => {
    const seqs = session.getSnapshot().nodes.map(n => n.seq)
    expect(seqs).toEqual([1, 3, 7, 9]) // both turns' user/assistant, no hole, no duplicate 9
  })
-
-  it('gap repair adopts the repull response projection (a missed todo/write outside the new tail page)', async () => {
-    const { api, session } = await opened(plainTurn(0, 0, 'a', 'b')) // tail seq = 5
-    expect(session.getSnapshot().todos).toEqual([])
-    // The missed range contained a todo/write that the repulled page no longer
-    // covers; the response's session-level projection is the only carrier.
-    const current = [{ content: '断线期间写的', status: 'in_progress' as const }]
-    api.onHistory = () => histResponse([...plainTurn(0, 0, 'a', 'b'), ...plainTurn(8, 1, 'c', 'd')], false, current)
-    session.handleMuxEnvelope('r' as never, { type: 'session/event', sessionId: SID, event: ev.assistant(11, 1, 'd') })
-    await vi.waitFor(() => {
-      expect(api.callsOf('session.history').length).toBe(2)
-    })
-    await Promise.resolve()
-    expect(session.getSnapshot().todos).toEqual(current)
-  })
-
-  it('clears the plan when a tail response omits the projection (a write the log never kept)', async () => {
-    // Live write lands, then the host crashes before persisting it: the
-    // authoritative log holds no todo/write, so the resync tail response
-    // carries no projection — an omitted field on a tail request is the empty
-    // list, not a missing carrier, and the rolled-back plan must disappear.
-    const { api, session } = await opened(plainTurn(0, 0, 'a', 'b'))
-    session.handleMuxEnvelope('r' as never, {
-      type: 'session/event', sessionId: SID,
-      event: ev.todoWrite(6, [{ content: '丢失的计划', status: 'in_progress' as const }]),
-    })
-    expect(session.getSnapshot().todos).toEqual([{ content: '丢失的计划', status: 'in_progress' }])
-    api.onHistory = () => histResponse(plainTurn(0, 0, 'a', 'b'))
-    await session.resync()
-    expect(session.getSnapshot().todos).toEqual([])
-  })
 })

 describe('paging', () => {
--- a/packages/client/runtime/tests/sessions-service.spec.ts
+++ b/packages/client/runtime/tests/sessions-service.spec.ts
@@ -47,7 +47,7 @@ describe('list store projection', () => {
    const b = bench()
    b.svc.handleMuxEnvelope({
      rpcId: 'title' as never,
-      payload: { type: 'session/title', sessionId: sid('s1'), title: 'Durable title', eventSeq: 2, updatedAt: 3 },
+      payload: { type: 'session/projection', sessionId: sid('s1'), key: 'title', value: 'Durable title', seq: 2 } as never,
    })
    await feedList(b, [
      { id: 's1', cwd: '/home/u/proj-a/' },
--- a/packages/client/runtime/tests/workspaces-service.spec.ts
+++ b/packages/client/runtime/tests/workspaces-service.spec.ts
@@ -236,6 +236,17 @@ describe('WorkspacesService', () => {
    expect(api.callsOf('host.pickDirectory')).toEqual([{}, {}])
  })

+  it('opens a filesystem path through the host without local state', async () => {
+    const ctx = new Context()
+    const api = new FakeApiClient()
+    const sessions = new SessionsService(ctx, api)
+    const workspaces = new WorkspacesService(ctx, api, sessions)
+    await expect(workspaces.openPath('/w/alpha/a.ts')).resolves.toBeUndefined()
+    expect(api.callsOf('host.openPath')).toEqual([{ path: '/w/alpha/a.ts' }])
+    api.onOpenPath = () => Promise.resolve(err({ code: 'internal', message: 'boom', details: {} }))
+    await expect(workspaces.openPath('/missing')).rejects.toThrow(/path open failed/)
+  })
+
  it('deletes a Workspace or preserves it when the Host rejects deletion', async () => {
    const ctx = new Context()
    const api = new FakeApiClient()
--- a/packages/client/runtime/tsconfig.json
+++ b/packages/client/runtime/tsconfig.json
@@ -23,6 +23,15 @@
    {
      "path": "../../host/apiproxy"
    },
+    {
+      "path": "../../ui/commands"
+    },
+    {
+      "path": "../../session-projection/session-projection"
+    },
+    {
+      "path": "../../session-title/session-title"
+    },
    {
      "path": "../../llm/llm"
    },