feat: add bounded diagnostics and improve UX feedback

Ask and Execute guidance, Runtime state, live announcements, loading states,
retry paths, settings focus, and update failures now provide consistent and
accessible feedback across the desktop experience.

Add bounded redacted Desktop and Agent diagnostic logs, a read-only Agent
diagnostics command, and an explicit opt-in for attaching a small Desktop
diagnostic summary to in-app feedback. Diagnostics stay local by default and
the existing feedback v1 service contract remains compatible.

Release note: 新增可选桌面诊断反馈与 Agent 诊断导出，并统一 Ask/Execute 状态、错误恢复和无障碍反馈；诊断默认保留在本地，仅在用户明确勾选时附加桌面摘要。

src/main/agent/runtime-controller.test.ts

@@ -106,7 +106,12 @@ describe('AgentRuntimeController', () => {
   it('fails retired runtime requests and disposes them after exit', async () => {
     const previous = new TestRuntime(true, true)
     const next = new TestRuntime()
-    const controller = new AgentRuntimeController(previous)
+    const observeFailure = vi.fn()
+    const controller = new AgentRuntimeController(
+      previous,
+      undefined,
+      observeFailure
+    )
     const authorize = vi.fn(async () => 'once' as const)
     const approvedStream = controller.run(
       {
@@ -137,6 +142,7 @@ describe('AgentRuntimeController', () => {
     await expect(controller.getStatus()).resolves.toMatchObject({
       label: 'Test'
     })
+    expect(observeFailure).not.toHaveBeenCalled()
   })
 
   it('keeps a retiring runtime alive until its status probe finishes', async () => {
@@ -449,6 +455,132 @@ describe('AgentRuntimeController', () => {
       expect(authorize).not.toHaveBeenCalled()
   })
 
+  it('does not report cancellation, AbortError, or tool denial', async () => {
+    const observeFailure = vi.fn()
+    const canceledRuntime = new TestRuntime()
+    canceledRuntime.run = async function* (
+      _request,
+      signal
+    ): AsyncGenerator<AgentEvent, void, void> {
+      yield* []
+      signal.throwIfAborted()
+      await new Promise<void>((_resolve, reject) => {
+        signal.addEventListener(
+          'abort',
+          () => reject(signal.reason),
+          { once: true }
+        )
+      })
+    }
+    const canceledController = new AgentRuntimeController(
+      canceledRuntime,
+      undefined,
+      observeFailure
+    )
+    const abortController = new AbortController()
+    const canceled = canceledController.run(
+      {
+        requestId: '1c608898-ecb7-4081-8174-2b6a52f53b18',
+        conversationId: 'conversation-canceled',
+        prompt: 'test',
+        workMode: 'ask'
+      },
+      abortController.signal
+    )
+    const pending = canceled.next()
+    abortController.abort()
+    await expect(pending).rejects.toMatchObject({
+      name: 'AbortError'
+    })
+    await canceledController.dispose()
+
+    const abortErrorRuntime = new TestRuntime()
+    abortErrorRuntime.run = async function* (): AsyncGenerator<
+      AgentEvent,
+      void,
+      void
+    > {
+      yield* []
+      throw new DOMException('aborted', 'AbortError')
+    }
+    const abortErrorController = new AgentRuntimeController(
+      abortErrorRuntime,
+      undefined,
+      observeFailure
+    )
+    const aborted = abortErrorController.run(
+      {
+        requestId: '1c608898-ecb7-4081-8174-2b6a52f53b19',
+        conversationId: 'conversation-abort-error',
+        prompt: 'test',
+        workMode: 'ask'
+      },
+      new AbortController().signal
+    )
+    await expect(aborted.next()).rejects.toMatchObject({
+      name: 'AbortError'
+    })
+    await abortErrorController.dispose()
+
+    const deniedRuntime = new TestRuntime(false, false, true)
+    const deniedController = new AgentRuntimeController(
+      deniedRuntime,
+      undefined,
+      observeFailure
+    )
+    const denied = deniedController.run(
+      {
+        requestId: '1c608898-ecb7-4081-8174-2b6a52f53b20',
+        conversationId: 'conversation-tool-denied',
+        prompt: 'test',
+        workMode: 'execute'
+      },
+      new AbortController().signal,
+      async () => 'deny'
+    )
+    await expect(denied.next()).rejects.toThrow('tool denied')
+    await deniedController.dispose()
+
+    expect(observeFailure).not.toHaveBeenCalled()
+  })
+
+  it('reports genuine Runtime run failures', async () => {
+    const runtime = new TestRuntime()
+    const failure = new Error('provider failed')
+    runtime.run = async function* (): AsyncGenerator<
+      AgentEvent,
+      void,
+      void
+    > {
+      yield* []
+      throw failure
+    }
+    const observeFailure = vi.fn()
+    const controller = new AgentRuntimeController(
+      runtime,
+      undefined,
+      observeFailure
+    )
+    const stream = controller.run(
+      {
+        requestId: '1c608898-ecb7-4081-8174-2b6a52f53b21',
+        conversationId: 'conversation-run-failed',
+        prompt: 'test',
+        workMode: 'ask'
+      },
+      new AbortController().signal
+    )
+
+    await expect(stream.next()).rejects.toBe(failure)
+    expect(observeFailure).toHaveBeenCalledWith({
+      component: 'runtime',
+      stage: 'run',
+      code: 'runtime.run.failed',
+      error: failure
+    })
+    await controller.dispose()
+  })
+
   it('forwards per-tool authorization without adding a whole-run gate', async () => {
     const runtime = new TestRuntime(false, false, true)
     const controller = new AgentRuntimeController(runtime)
@@ -490,4 +622,26 @@ describe('AgentRuntimeController', () => {
       '当前 Runtime 不支持工具执行'
     )
   })
+
+  it('reports Runtime boundary failures without request content', async () => {
+    const runtime = new TestRuntime()
+    const failure = new Error('provider raw response: secret prompt')
+    runtime.getStatus = vi.fn(async () => {
+      throw failure
+    })
+    const observeFailure = vi.fn()
+    const controller = new AgentRuntimeController(
+      runtime,
+      undefined,
+      observeFailure
+    )
+
+    await expect(controller.getStatus()).rejects.toBe(failure)
+    expect(observeFailure).toHaveBeenCalledWith({
+      component: 'runtime',
+      stage: 'status',
+      code: 'runtime.operation.failed',
+      error: failure
+    })
+  })
 })