fix(trajectory): preserve state across history prepends

packages/client/runtime/README.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/client/runtime/README.md
-README.md: 3e9bcdd587764ee21326c27e0cd642914cf84f8f
-README.zh.md: 8e13bc3d09ae220f7a64640b21892c03a37bae29
+README.md: f5dd94bc1c937b69d74f450f11bf875b50af4c62
+README.zh.md: 270d2d41e266fe198f91a939eba946e2f86844d9

packages/client/runtime/README.md

@@ -2,7 +2,7 @@
 
 English | [中文](README.zh.md)
 
-Client cordis boot and React-free object services: SlotsService wraps SlotCore and supplies renderer data sources; SessionsService owns Session objects and the Chat-facing list, scope, and event-window state; SessionHistoryService lazily owns independent raw-history ledgers for inspection consumers, loading the current tail first and prepending one older page only when its consumer requests it; WorkspacesService depends on SessionsService and owns Workspace objects, list/actions, default-target derivation, and the New Session blank-reuse entry (`connectWorkspace`). The runtime fans the shared Host stream into the Session, Workspace, and activated history owners without routing inspection state through Session or SessionManager, and bridges the registry-invalidation frames to typed ctx events (`commands/changed`, `settings/changed`, `credentials/changed`, `models/changed`) so surface caches refetch without touching the stream. Client sessions are always Host-born (Session+Agent+cwd in one `session.create`); the client holds no pre-entity session state — a session's Agent scope (the client mirror of host dsh-scope, keyed by the shared agent/session id) is born when its row enters the list mirror and dies with the prune. Contract: api-contracts v3 §4. Each `Session` holds a generic `ProjectionValueStore` seeded from the history-tail `projections` block and updated by `session/projection` frames under higher-seq-wins; domain keys (including `todos`) are read via `projections.faceOf` / `useProjection`, not via `ConversationSnapshot`. The store also publishes one reference-stable whole-value map through `SessionSummary.projectionValues`, allowing global list consumers to reuse the same projections without creating per-session subscriptions.
+Client cordis boot and React-free object services: SlotsService wraps SlotCore and supplies renderer data sources; SessionsService owns Session objects and the Chat-facing list, scope, and event-window state; SessionHistoryService lazily owns independent raw-history ledgers for inspection consumers, loading the current tail first and prepending one older page only when its consumer requests it. Each history snapshot exposes the raw window's absolute base sequence so a consumer detects a prepend even when the page adds no surface-visible node. WorkspacesService depends on SessionsService and owns Workspace objects, list/actions, default-target derivation, and the New Session blank-reuse entry (`connectWorkspace`). The runtime fans the shared Host stream into the Session, Workspace, and activated history owners without routing inspection state through Session or SessionManager, and bridges the registry-invalidation frames to typed ctx events (`commands/changed`, `settings/changed`, `credentials/changed`, `models/changed`) so surface caches refetch without touching the stream. Client sessions are always Host-born (Session+Agent+cwd in one `session.create`); the client holds no pre-entity session state — a session's Agent scope (the client mirror of host dsh-scope, keyed by the shared agent/session id) is born when its row enters the list mirror and dies with the prune. Contract: api-contracts v3 §4. Each `Session` holds a generic `ProjectionValueStore` seeded from the history-tail `projections` block and updated by `session/projection` frames under higher-seq-wins; domain keys (including `todos`) are read via `projections.faceOf` / `useProjection`, not via `ConversationSnapshot`. The store also publishes one reference-stable whole-value map through `SessionSummary.projectionValues`, allowing global list consumers to reuse the same projections without creating per-session subscriptions.
 
 ## Workspace and Session lists
 

packages/client/runtime/README.zh.md

@@ -2,7 +2,7 @@
 
 [English](README.md) | 中文
 
-客户端 cordis 启动与不依赖 React 的对象服务：SlotsService 包装 SlotCore 并提供 renderer 数据源；SessionsService 拥有 Session 对象以及 Chat 所需的列表、scope 和事件窗口状态；SessionHistoryService 为检查类消费方惰性拥有彼此独立的原始历史账本，先加载当前尾部，并仅在消费方请求时向前补入一页更早历史；WorkspacesService 依赖 SessionsService，拥有 Workspace 对象、列表／操作、默认目标派生，以及 New Session 空会话复用入口（`connectWorkspace`）。运行时把共享 Host 流分发给 Session、Workspace 和已激活的历史数据所有者，不让检查状态经过 Session 或 SessionManager，并把注册表失效帧桥接为类型化 ctx 事件（`commands/changed`、`settings/changed`、`credentials/changed`、`models/changed`），使各表面缓存无需触碰流即可重拉。客户端会话一律由 Host 创建（一次 `session.create` 同时产生 Session、agent（智能体）和 cwd）；客户端不持有任何实体化之前的会话状态——agent scope（host dsh-scope 的客户端镜像，以 agent/session 共用 id 为键）在会话行进入列表镜像时创建，并随 prune 销毁。契约：api-contracts v3 §4。每个 `Session` 持有一个通用的 `ProjectionValueStore`，由历史记录尾部的 `projections` 块播种，并经 `session/projection` 帧按 seq 高者胜更新；领域键（含 `todos`）经 `projections.faceOf`／`useProjection` 读取，不经 `ConversationSnapshot`。该 store 还会通过 `SessionSummary.projectionValues` 发布一份引用稳定的完整值映射，使全局列表消费方无需为每个会话创建订阅，即可复用同一组投影。
+客户端 cordis 启动与不依赖 React 的对象服务：SlotsService 包装 SlotCore 并提供 renderer 数据源；SessionsService 拥有 Session 对象以及 Chat 所需的列表、scope 和事件窗口状态；SessionHistoryService 为检查类消费方惰性拥有彼此独立的原始历史账本，先加载当前尾部，并仅在消费方请求时向前补入一页更早历史。每份历史快照都会公开原始窗口的绝对基准序号，因此即使该页没有新增任何 surface 可见节点，消费方仍能检测到向前补页。WorkspacesService 依赖 SessionsService，拥有 Workspace 对象、列表／操作、默认目标派生，以及 New Session 空会话复用入口（`connectWorkspace`）。运行时把共享 Host 流分发给 Session、Workspace 和已激活的历史数据所有者，不让检查状态经过 Session 或 SessionManager，并把注册表失效帧桥接为类型化 ctx 事件（`commands/changed`、`settings/changed`、`credentials/changed`、`models/changed`），使各表面缓存无需触碰流即可重拉。客户端会话一律由 Host 创建（一次 `session.create` 同时产生 Session、agent（智能体）和 cwd）；客户端不持有任何实体化之前的会话状态——agent scope（host dsh-scope 的客户端镜像，以 agent/session 共用 id 为键）在会话行进入列表镜像时创建，并随 prune 销毁。契约：api-contracts v3 §4。每个 `Session` 持有一个通用的 `ProjectionValueStore`，由历史记录尾部的 `projections` 块播种，并经 `session/projection` 帧按 seq 高者胜更新；领域键（含 `todos`）经 `projections.faceOf`／`useProjection` 读取，不经 `ConversationSnapshot`。该 store 还会通过 `SessionSummary.projectionValues` 发布一份引用稳定的完整值映射，使全局列表消费方无需为每个会话创建订阅，即可复用同一组投影。
 
 ## Workspace 与 Session 列表
 

packages/client/runtime/src/client/contract/session-history.ts

@@ -9,6 +9,8 @@ export interface SessionHistorySnapshot {
   state: 'cold' | 'loading' | 'ready' | 'error'
   error: RpcError | null
   hasMore: boolean
+  /** Absolute sequence of the first loaded raw event, or zero for an empty window. */
+  baseSeq: number
   inspection: SessionHistoryInspection
 }
 

packages/client/runtime/src/client/session-history/source.ts

@@ -97,11 +97,6 @@ export class SessionHistorySource implements SessionHistoryFace {
     return this.baseSeq !== previousBaseSeq
   }
 
-  /** Rebuild the tail for whichever mounted consumers survive a reconnect. */
-  private async loadForConsumers(): Promise<void> {
-    await this.open()
-  }
-
   /**
    * Route a relevant mux frame without involving the Chat session.
    * @param frame - Session-addressed frame.
@@ -145,7 +140,7 @@ export class SessionHistorySource implements SessionHistoryFace {
     this.state = 'cold'
     this.error = null
     this.publishDirtyNow()
-    void this.loadForConsumers()
+    void this.open()
   }
 
   /** Stop future refresh work after the host removes the session. */
@@ -408,6 +403,7 @@ export class SessionHistorySource implements SessionHistoryFace {
       state: this.state,
       error: this.error,
       hasMore: this.hasMore,
+      baseSeq: this.baseSeq,
       inspection: this.currentInspection(),
     }
   }

packages/client/runtime/tests/session-history-source.spec.ts

@@ -34,6 +34,7 @@ describe('SessionHistorySource', () => {
 
     expect(api.callsOf('session.history')).toHaveLength(1)
     expect(source.getSnapshot().hasMore).toBe(true)
+    expect(source.getSnapshot().baseSeq).toBe(12)
     expect(source.getSnapshot().inspection.eventNodes.map(node => node.seq))
       .toEqual([13, 15])
 
@@ -43,6 +44,7 @@ describe('SessionHistorySource', () => {
 
     expect(api.callsOf('session.history')).toHaveLength(3)
     expect(source.getSnapshot().hasMore).toBe(false)
+    expect(source.getSnapshot().baseSeq).toBe(0)
     expect(source.getSnapshot().inspection.eventNodes.map(node => node.seq))
       .toEqual([1, 3, 7, 9, 13, 15])
   })