fix(native-chat): a stop-all that times out stops asking, and "no children" is sent once

A stop-all kept asking after a request timed out, so a Claude CLI that stopped
answering control requests cost one full deadline per task, while the chat's
sends, Stop and /compact waited behind it. A timeout now ends the loop; other
request failures still let the remaining tasks be stopped.

The chat strip channel never remembered that it had sent "no children", so
every change in a chat with none re-sent that frame to each subscriber. It now
remembers it, and forgets only when the conversation closes.

Also renames agent-child-work-stop.ts to agent-child-work-stop-targets.ts, which
says what it answers: the provider ids a background Stop reaches.

src/main/claude/claude-background-stop-records.test.ts

@@ -3,7 +3,7 @@
 // order through the real adapter and a real hook server.
 
 import { afterEach, describe, expect, it, vi } from 'vitest'
-import { agentChildWorkStopTargets } from '../../shared/agent-child-work-stop'
+import { agentChildWorkStopTargets } from '../../shared/agent-child-work-stop-targets'
 import type { AgentSessionRecord } from '../../shared/agent-session-record'
 import { conversationCommandBlocked } from '../native-chat/agent-session-wire/structured-conversation-command-admission'
 import type { CapturedFrame } from './claude-captured-frame-builders.test-fixture'

src/main/claude/claude-structured-control-actions.test.ts

@@ -6,6 +6,10 @@ import {
 } from './claude-structured-control-actions'
 import { dispatchClaudeTurn } from './claude-structured-dispatch'
 import { ClaudeControlRequestError } from './claude-stream-json-connection'
+import {
+  ClaudeControlRequestTimeoutError,
+  runClaudeControl
+} from './claude-agent-sdk-control-requests'
 import { buildClaudePromptReply, ClaudePromptRegistry } from './claude-structured-prompt-replies'
 import type { ClaudeDispatchWaiter, ClaudeSession } from './claude-structured-session-state'
 import { ClaudeChildWorkDecoder } from './claude-child-work-decoder'
@@ -389,4 +393,25 @@ describe('stopClaudeBackgroundTasks', () => {
       { type: 'ended', handle: { id: 'task-2' }, outcome: 'cancelled' }
     ])
   })
+
+  it('stops asking after a request times out: a CLI not answering costs one deadline, not one per task', async () => {
+    const childWork = liveChildWork(['task-0', 'task-1', 'task-2', 'task-3', 'task-4'])
+    // Never answered, behind the real deadline wrapper, with a short deadline.
+    const stopTask = vi.fn((_taskId: string, options?: { timeoutMs?: number }) =>
+      runClaudeControl('stop_task', () => new Promise<void>(() => {}), options?.timeoutMs)
+    )
+    const session = stoppingSession(childWork, stopTask)
+
+    await expect(
+      stopClaudeBackgroundTasks(session, 50, () => true, [
+        'task-0',
+        'task-1',
+        'task-2',
+        'task-3',
+        'task-4'
+      ])
+    ).rejects.toBeInstanceOf(ClaudeControlRequestTimeoutError)
+    expect(stopTask).toHaveBeenCalledTimes(1)
+    expect(childWork.drain(2)).toEqual([])
+  })
 })

src/main/claude/claude-structured-control-actions.ts

@@ -1,6 +1,7 @@
 import type { PermissionResult } from '@anthropic-ai/claude-agent-sdk'
 import type { ClaudePromptClaim } from './claude-structured-prompt-replies'
 import { ClaudeControlRequestError } from './claude-stream-json-connection'
+import { ClaudeControlRequestTimeoutError } from './claude-agent-sdk-control-requests'
 import { settleCancelledClaudeDispatchWaiters } from './claude-structured-dispatch'
 import type { ClaudeLateDispatchSettlement } from './claude-replay-turn-resolution'
 import type { ClaudeSession } from './claude-structured-session-state'
@@ -67,7 +68,9 @@ export async function stopClaudeBackgroundTasks(
   taskIds: readonly string[]
 ): Promise<{ cancelled: boolean }> {
   let cancelled = false
-  // A failed request for one task still leaves the others to stop; it is reported after them.
+  // A failed request for one task still leaves the others to stop; it is reported after them. A
+  // timeout ends the loop: a CLI that is not answering would make each id wait out its own
+  // deadline while the session's other actions queue behind this one.
   let failure: { error: unknown } | undefined
   for (const taskId of taskIds) {
     if (!isCurrent()) {
@@ -78,6 +81,9 @@ export async function stopClaudeBackgroundTasks(
       session.childWork.stopAcknowledged(taskId)
       cancelled = true
     } catch (error) {
+      if (error instanceof ClaudeControlRequestTimeoutError) {
+        throw error
+      }
       if (!(error instanceof ClaudeControlRequestError)) {
         failure ??= { error }
       }

src/main/native-chat/agent-session-wire/structured-agent-session-background-task-channel.test.ts

@@ -23,7 +23,7 @@ const child: AgentChildWorkView = {
   invocation: { invocationId: 'spawn-1', generation: 1 }
 }
 
-function channelOver() {
+function channelOver(children: () => AgentChildWorkView[] = () => [child]) {
   const sessions = new StructuredAgentSessionConversations({
     deliver: () => {},
     onDeliveryError: () => {},
@@ -42,7 +42,7 @@ function channelOver() {
     async () => {
       throw new Error('not opened here')
     },
-    () => [child]
+    children
   )
   // oxlint-disable-next-line typescript/consistent-type-assertions -- SAFETY: the map reads only the journal's commit observer and the session's provider.
   const session = {
@@ -67,4 +67,24 @@ describe('the background-task channel', () => {
     channel.publish('session-1')
     expect(sent).toHaveBeenCalledTimes(2)
   })
+
+  it('sends "no children" once, not again on every change that leaves none', () => {
+    let views: AgentChildWorkView[] = []
+    const { sessions, sent, channel, session } = channelOver(() => views)
+    sessions.set('session-1', session)
+    channel.publish('session-1')
+    channel.publish('session-1')
+    expect(sent.mock.calls.map(([, state]) => state)).toEqual([null])
+
+    views = [child]
+    channel.publish('session-1')
+    views = []
+    channel.publish('session-1')
+    channel.publish('session-1')
+    expect(sent.mock.calls.map(([, state]) => state?.children?.length ?? null)).toEqual([
+      null,
+      1,
+      null
+    ])
+  })
 })

src/main/native-chat/agent-session-wire/structured-agent-session-background-task-channel.ts

@@ -85,7 +85,7 @@ export class StructuredAgentSessionBackgroundTaskChannel {
   /** Re-read after the session's child records changed; an unchanged roster sends nothing. */
   publish(sessionId: string): void {
     const session = this.sessions.get(sessionId)
-    // Explicit null once rows were sent, not silence: a reader keeps its last roster on
+    // Explicit null once a roster was sent, not silence: a reader keeps its last roster on
     // `undefined`, and a closing provider stops answering before its records are gone.
     const read = this.state(sessionId)
     const state = read === undefined && this.published.has(sessionId) ? null : read
@@ -96,11 +96,9 @@ export class StructuredAgentSessionBackgroundTaskChannel {
     if (this.published.get(sessionId) === fingerprint) {
       return
     }
-    if (state === null) {
-      this.published.delete(sessionId)
-    } else {
-      this.published.set(sessionId, fingerprint)
-    }
+    // "None" is remembered too, so a session with no children sends it once, not on every change;
+    // the entry goes when the conversation closes.
+    this.published.set(sessionId, fingerprint)
     this.subscribers.backgroundTasks(
       sessionId,
       state,

src/main/native-chat/agent-session-wire/structured-agent-session-turns-cancel.ts

@@ -1,4 +1,4 @@
-import { agentChildWorkStopTargets } from '../../../shared/agent-child-work-stop'
+import { agentChildWorkStopTargets } from '../../../shared/agent-child-work-stop-targets'
 import { agentSessionFailureFact } from '../../../shared/agent-session-failure'
 import type { AgentChildWorkView } from '../../../shared/agent-status-child-work-view'
 import { agentSessionFailureWords } from '../../../shared/agent-session-failure-words'

src/main/native-chat/agent-session-wire/structured-conversation-command-admission.ts

@@ -1,4 +1,4 @@
-import { agentChildWorkViewOffersStop } from '../../../shared/agent-child-work-stop'
+import { agentChildWorkViewOffersStop } from '../../../shared/agent-child-work-stop-targets'
 import type { AgentSessionRecord } from '../../../shared/agent-session-record'
 import { isQueuedAgentJournalSubmission } from '../../../shared/agent-session-queued-submission'
 import { agentChildWorkLiveness } from '../../../shared/agent-status-child-work-liveness'

src/shared/agent-child-row-model.ts

@@ -19,7 +19,7 @@ import {
   deriveAgentChildDisplayState,
   type AgentChildDisplayState
 } from './agent-status-child-work-display'
-import { agentChildWorkViewOffersStop } from './agent-child-work-stop'
+import { agentChildWorkViewOffersStop } from './agent-child-work-stop-targets'
 import type { AgentChildWorkView } from './agent-status-child-work-view'
 import {
   agentStatusAuthorityObservedAt,