feat(web): split context injection into producer-declared forms

Injected context reached the transcript as one anonymous shape whose
expanded body was the whole message serialized as inline JSON, so the
escaping collapsed the only readable part — the model-facing prose —
into a single line.

`MessageSource` gains an optional producer-declared `form`, a small
semantic vocabulary of information shapes independent of `kind`: kind
says who produced the context, form says what shape it is, so several
producers may share one presentation. Two values ship.

`instructions` (workspace-context) lists the reconciled files above
their text and keeps the `<system-reminder>` framing verbatim, because
the framing is part of what the model read. `catalog` moves dsh-tool-skill
off the shared plugin kind onto a `skill-catalog` source carrying the
published name/description entries, and the body lists those instead of
re-parsing `<available_skills>` out of the prose. Catalog identity moves
with it: the republish digest now covers the durable entries, deleting
the text-slicing that recovered them from a logged message.

Everything else renders the opaque body — the model-facing text with its
real line breaks, then the remaining provenance as fields. That is the
documented default, not a leftover: a resumed, forked, or foreign log
must render whether or not its producer is mounted here, which is why
the classification lives in the durable source rather than a client-side
table keyed by producer.

packages/client/runtime/src/client/index.ts

@@ -53,7 +53,9 @@ export type {
 export type {
   ConversationContext, ConversationContextOriginKind,
 } from './sessions/conversation-context.ts'
-export type { ContextProvenanceView, ContextRole } from './sessions/context-provenance.ts'
+export type {
+  ContextProvenanceView, ContextRole, KnownContextForm,
+} from './sessions/context-provenance.ts'
 export type {
   ConversationPromptSnapshot, RequestInspectionSnapshot, RequestPromptChange, RequestView,
 } from './sessions/request-inspection.ts'

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

@@ -11,7 +11,7 @@ import type {
   PartialAssistant, RunningToolCall,
 } from '../sessions/conversation.ts'
 import { toAssistantBlocks } from '../sessions/conversation.ts'
-import { contextProvenance } from '../sessions/context-provenance.ts'
+import { contextForm, contextProvenance } from '../sessions/context-provenance.ts'
 import type {
   ConversationContext, ConversationContextOriginKind,
 } from '../sessions/conversation-context.ts'
@@ -128,6 +128,7 @@ function materializeNode(
           kind: 'context', seq: event.seq, time: event.time,
           content: event.data.content, source: event.data.source,
           provenance: contextProvenance(event.data.source),
+          form: contextForm(event.data.source),
         }
       }
       return {

packages/client/runtime/src/client/sessions/context-provenance.ts

@@ -89,3 +89,28 @@ export function contextProvenance(source: unknown): ContextProvenanceView {
       return { role: 'inject', label: kind }
   }
 }
+
+/**
+ * Context forms this UI version renders with a dedicated presentation. The
+ * durable vocabulary (`ContextForm` in `dsh-llm`) may already be wider — an
+ * unrecognized or absent value degrades to the opaque presentation rather than
+ * dropping the row, so a log written by a newer or foreign producer still
+ * renders.
+ */
+const KNOWN_FORMS = ['instructions', 'catalog'] as const
+
+/** One durable context form this UI version knows how to present. */
+export type KnownContextForm = typeof KNOWN_FORMS[number]
+
+/**
+ * Read the producer-declared form off one durable message source.
+ * @param source - the logged `user/message` source, exactly as recorded.
+ * @returns the form when this UI version presents it, otherwise null (opaque).
+ */
+export function contextForm(source: unknown): KnownContextForm | null {
+  const record = asRecord(source)
+  const form = record === null ? null : readString(record, 'form')
+  return form !== null && (KNOWN_FORMS as readonly string[]).includes(form)
+    ? form as KnownContextForm
+    : null
+}

packages/client/runtime/src/client/sessions/conversation.ts

@@ -12,7 +12,7 @@ import type {
   InboxItemId, RpcError, SessionId, SubagentAddress, ToolCallView, ToolResultView,
 } from '@deepseek-ai/dsh-client-connection/client'
 import type { PendingInteraction } from './pending.ts'
-import type { ContextProvenanceView } from './context-provenance.ts'
+import type { ContextProvenanceView, KnownContextForm } from './context-provenance.ts'
 export type { TodoItem }
 
 /** Request configuration recorded for one provider call. */
@@ -126,6 +126,8 @@ export interface ContextMessageNode {
   source: unknown
   /** Role and producer name projected from `source` ({@link contextProvenance}). */
   provenance: ContextProvenanceView
+  /** Producer-declared information form ({@link contextForm}); null presents as opaque. */
+  form: KnownContextForm | null
 }
 
 /** Durable notice that a closed failed step is waiting for a model-request retry. */

packages/client/runtime/src/client/sessions/transcript-adapter.ts

@@ -22,7 +22,7 @@ import type { COMPACT_CHECKPOINT_SOURCE } from '@deepseek-ai/dsh-compact/checkpo
 import type { ToolCallView, ToolEventView, ToolResultView } from '@deepseek-ai/dsh-client-connection/client'
 import type { CommandNode, CompactionSummaryNode, ConversationNode } from './conversation.ts'
 import { toAssistantBlocks } from './conversation.ts'
-import { contextProvenance } from './context-provenance.ts'
+import { contextForm, contextProvenance } from './context-provenance.ts'
 
 /**
  * The compaction seam's checkpoint plugin, pinned to the seam's own declaration
@@ -62,6 +62,7 @@ function materializeNode(
           kind: 'context', seq: event.seq, time: event.time,
           content: event.data.content, source: event.data.source,
           provenance: contextProvenance(event.data.source),
+          form: contextForm(event.data.source),
         }
       }
       return {