feat(web): add basic past-session search (round 1)

packages/client/runtime/tests/fake-api.ts

@@ -3,7 +3,7 @@
 // deferred-controlled timing). Streams are hand pumps: pushMux/pushHost.
 import type {
   ClientResponse, CommandDescriptor, CommandExecuteResult, HostFrame, IApiClient, MuxFrame,
-  RpcError, RpcReceipt, RpcRequest, RpcResponse, SessionId, SkillEntry,
+  RpcError, RpcReceipt, RpcRequest, RpcResponse, SessionId, SessionSearchItem, SkillEntry,
   WorkspaceId, WorkspaceView,
 } from '@deepseek-ai/dsh-client-connection/client'
 import { RpcId } from '@deepseek-ai/dsh-client-connection/client'
@@ -60,6 +60,8 @@ export class FakeApiClient implements IApiClient {
 
   // Programmable slots (defaults answer OK-empty); reassign per case.
   onList: (payload: unknown) => Promise<RpcResponse<{ items: never[] }>> = () => Promise.resolve(ok({ items: [] }))
+  onSearch: (payload: unknown) => Promise<RpcResponse<{ items: SessionSearchItem[]; hasMore: boolean }>> =
+    () => Promise.resolve(ok({ items: [], hasMore: false }))
   onCreate: (payload: unknown) => Promise<RpcResponse<{ sessionId: SessionId }>> = () => Promise.resolve(ok({ sessionId: 'fk-new' as SessionId }))
   onHistory: (payload: { sessionId: SessionId; beforeSeq?: number; maxMessages?: number })
   => Promise<RpcResponse<{ events: never[]; hasMore: boolean }>> =
@@ -72,12 +74,17 @@ export class FakeApiClient implements IApiClient {
 
   private readonly muxConns: StreamConn<MuxFrame>[] = []
   private readonly hostConns: StreamConn<HostFrame>[] = []
+  lastSearchSignal: AbortSignal | undefined
 
   // Parameters carry local structural annotations: the CI lint lane runs
   // without built lib/, so IApiClient's indexed-access types collapse to any
   // and inferred parameters would trip no-unsafe-argument.
   readonly sessions: IApiClient['sessions'] = {
     list: (payload: unknown) => this.record('session.list', payload, this.onList(payload)),
+    search: (payload: unknown, signal?: AbortSignal) => {
+      this.lastSearchSignal = signal
+      return this.record('session.search', payload, this.onSearch(payload))
+    },
     create: (payload: unknown) => this.record('session.create', payload, this.onCreate(payload)),
     history: (payload: { sessionId: SessionId; beforeSeq?: number; maxMessages?: number }) =>
       this.record('session.history', payload, this.onHistory(payload)),

packages/client/runtime/tests/manager.spec.ts

@@ -194,6 +194,49 @@ describe('list lifecycle', () => {
   })
 })
 
+describe('search', () => {
+  it('returns bounded Host results and forwards the caller signal', async () => {
+    const api = new FakeApiClient()
+    api.onSearch = () => Promise.resolve(ok({
+      items: [{ sessionId: S1, snippet: 'matching excerpt' }],
+      hasMore: true,
+    }))
+    const manager = new SessionManager(api)
+    const signal = new AbortController().signal
+
+    await expect(manager.search('exact phrase', signal)).resolves.toEqual({
+      ok: true,
+      value: {
+        items: [{ sessionId: S1, snippet: 'matching excerpt' }],
+        hasMore: true,
+      },
+    })
+    expect(api.callsOf('session.search')).toEqual([{ query: 'exact phrase' }])
+    expect(api.lastSearchSignal).toBe(signal)
+  })
+
+  it('preserves business errors and folds transport failures', async () => {
+    const api = new FakeApiClient()
+    const manager = new SessionManager(api)
+    api.onSearch = () => Promise.resolve(err({
+      code: 'internal',
+      message: 'index unavailable',
+      details: {},
+    }))
+    const signal = new AbortController().signal
+    await expect(manager.search('first', signal)).resolves.toMatchObject({
+      ok: false,
+      error: { code: 'internal', message: 'index unavailable' },
+    })
+
+    api.onSearch = () => Promise.reject(new Error('wire down'))
+    await expect(manager.search('second', signal)).resolves.toMatchObject({
+      ok: false,
+      error: { code: 'internal', message: 'wire down' },
+    })
+  })
+})
+
 describe('host frame routing', () => {
   it('adds/removes/flips sessions from host frames and keeps removed instances resident', async () => {
     const api = new FakeApiClient()

packages/client/runtime/tests/sessions-service.spec.ts

@@ -69,6 +69,29 @@ describe('list store projection', () => {
   })
 })
 
+describe('search', () => {
+  it('delegates transient content search without changing the list snapshot', async () => {
+    const b = bench()
+    await feedList(b, [{ id: 's1' }])
+    const before = b.svc.list.getSnapshot()
+    b.api.onSearch = () => Promise.resolve(ok({
+      items: [{ sessionId: sid('s1'), snippet: 'matching excerpt' }],
+      hasMore: false,
+    }))
+    const signal = new AbortController().signal
+
+    await expect(b.svc.search('needle', signal)).resolves.toEqual({
+      ok: true,
+      value: {
+        items: [{ sessionId: 's1', snippet: 'matching excerpt' }],
+        hasMore: false,
+      },
+    })
+    expect(b.api.lastSearchSignal).toBe(signal)
+    expect(b.svc.list.getSnapshot()).toBe(before)
+  })
+})
+
 describe('scope tree', () => {
   it('mints lazily on first resolution, tags the ctx, and keeps binding identity stable', async () => {
     const b = bench()