feat(web): render durable session titles

packages/host/apiproxy/src/api/events.schema.ts

@@ -25,6 +25,7 @@ export const askUserQuestionItemSchema = z.object({
 export const muxFrameSchema = z.discriminatedUnion('type', [
   z.object({ type: z.literal('session/event'), sessionId: sessionIdSchema, event: sessionEventSchema, view: toolEventViewSchema.optional() }),
   z.object({ type: z.literal('session/subscribed'), sessionId: sessionIdSchema, lastSeq: z.number().int() }),
+  z.object({ type: z.literal('session/title'), sessionId: sessionIdSchema, title: z.string().min(1), eventSeq: z.number().int().nonnegative(), updatedAt: z.number() }),
   z.object({ type: z.literal('approval/requested'), sessionId: sessionIdSchema, approvalId: approvalRequestIdSchema, toolName: z.string(), callId: z.string().optional(), reason: z.string().optional() }),
   z.object({ type: z.literal('approval/resolved'), sessionId: sessionIdSchema, approvalId: approvalRequestIdSchema, outcome: z.union([z.literal('allowed-once'), z.literal('rejected'), z.literal('cancelled'), z.literal('unavailable')]) }),
   z.object({ type: z.literal('question/requested'), sessionId: sessionIdSchema, questions: z.array(askUserQuestionItemSchema) }),

packages/host/apiproxy/src/api/events.ts

@@ -33,8 +33,9 @@ export type ToolEventView =
 export interface EventsApi {
   /**
    * All-session aggregated mux stream. On open, emits a subscribed control frame for every
-   * attached session and replays each session's still-pending approval/question requested
-   * frames (rpcId reused verbatim — the refresh-recovery baseline).
+   * attached session followed by its optional latest title snapshot, then replays each
+   * session's still-pending approval/question requested frames (rpcId reused verbatim — the
+   * refresh-recovery baseline).
    * since: resume seam, unimplemented in v1 (ignored if passed); reconnection = reopen the
    * stream + refetch history.
    */
@@ -54,6 +55,7 @@ export interface EventsApi {
 export type MuxFrame =
   | { type: 'session/event'; sessionId: SessionId; event: SessionEvent; view?: ToolEventView }
   | { type: 'session/subscribed'; sessionId: SessionId; lastSeq: number }
+  | { type: 'session/title'; sessionId: SessionId; title: string; eventSeq: number; updatedAt: number }
   | { type: 'approval/requested'; sessionId: SessionId; approvalId: ApprovalRequestId; toolName: string; callId?: CallId; reason?: string }
   | { type: 'approval/resolved'; sessionId: SessionId; approvalId: ApprovalRequestId; outcome: ApprovalOutcome }
   | { type: 'question/requested'; sessionId: SessionId; questions: AskUserQuestionItem[] }

packages/host/apiproxy/tests/rpc-schemas.spec.ts

@@ -123,6 +123,7 @@ describe('events frame schemas', () => {
     const frames = [
       { type: 'session/event', sessionId: 's', event: { type: 't', seq: 0, time: 1, data: null } },
       { type: 'session/subscribed', sessionId: 's', lastSeq: -1 },
+      { type: 'session/title', sessionId: 's', title: 'Durable title', eventSeq: 2, updatedAt: 3 },
       { type: 'approval/requested', sessionId: 's', approvalId: 'a', toolName: 'bash', callId: 'c', reason: 'r' },
       { type: 'approval/resolved', sessionId: 's', approvalId: 'a', outcome: 'allowed-once' },
       { type: 'question/requested', sessionId: 's', questions: [{ id: 'q', question: 'Q?', options: [{ label: 'L' }], multiSelect: true }] },
@@ -131,6 +132,13 @@ describe('events frame schemas', () => {
     ]
     for (const frame of frames) expect(muxFrameSchema.parse(frame)).toMatchObject({ type: frame.type })
     expect(() => muxFrameSchema.parse({ type: 'unknown/frame' })).toThrow()
+    for (const invalid of [
+      { type: 'session/title', sessionId: 's', title: '', eventSeq: 0, updatedAt: 1 },
+      { type: 'session/title', sessionId: 's', title: 'x', eventSeq: -1, updatedAt: 1 },
+      { type: 'session/title', sessionId: 's', title: 'x', eventSeq: 0.5, updatedAt: 1 },
+      { type: 'session/title', sessionId: 's', title: 'x', eventSeq: 0, updatedAt: 'now' },
+      { type: 'session/title', sessionId: 's', title: 'x', eventSeq: 0, updatedAt: Number.NaN },
+    ]) expect(() => muxFrameSchema.parse(invalid)).toThrow()
     expect(askUserQuestionItemSchema.parse({ id: 'q', question: 'Q?' }).id).toBe('q')
   })