fix: 遵守仓库硬约束（禁止修改 DSH 源码）——tasks.output 改为会话事件回放

- 回退对 harness peek 缝隙的依赖：输出查看不再调用注册表，改为从属主
  会话事件日志回放 task_output 的 tool/call+tool/result 对（模型已读内容）
- read:false 时面板提示「模型尚未读取」；'(no new output)' 增量与错误
  结果过滤；截断上限不变；kill 走注册表原生 API（缺席时 503）
- AGENTS.md 新增 §0 硬约束：禁止修改 DSH 源码、挂载只走 cordis.patch.yml
  + profile 机制；设计文档同步实施偏差
- 测试：tasks-routes 重写为回放语义（拼接/过滤/read 标志/截断/503），
  视图新增 read:false 提示用例；全量 369 通过

tests/subagent-tasks-view.spec.tsx

@@ -99,7 +99,15 @@ beforeEach(() => {
     const body = JSON.parse(String(init?.body)) as { sessionId: string; id: string }
     if (method === 'tasks.output') {
       outputCalls.push({ sessionId: body.sessionId, id: body.id })
-      return jsonResponse({ ok: true, value: { text: `output-of-${body.id}`, truncated: false, status: 'running' } })
+      // bash-9 stands for a task the model never read (read:false).
+      return jsonResponse({
+        ok: true,
+        value: {
+          text: body.id === 'bash-9' ? '' : `output-of-${body.id}`,
+          truncated: false,
+          read: body.id !== 'bash-9',
+        },
+      })
     }
     if (method === 'tasks.kill') {
       killCalls.push({ sessionId: body.sessionId, id: body.id })
@@ -192,7 +200,7 @@ describe('SubagentView background tasks', () => {
     expect(container.textContent).toContain('output-of-bash-1')
     const second = container.querySelector('button[aria-label*="echo hi"]') as HTMLButtonElement
     await act(async () => { second.click() })
-    // One dock, now fed by the second task (its owner session scopes the peek).
+    // One dock, now fed by the second task (its owner session scopes the replay).
     expect(outputCalls).toEqual([
       { sessionId: 'root', id: 'bash-1' },
       { sessionId: 'child', id: 'bash-2' },
@@ -203,6 +211,26 @@ describe('SubagentView background tasks', () => {
     unmount()
   })
 
+  it('explains when the model has not read the task yet', async () => {
+    const snapshot = baseSnapshot()
+    snapshot.tasksBySession = {
+      root: [
+        ...(snapshot.tasksBySession?.root ?? []),
+        { id: 'bash-9', kind: 'bash', label: 'unread cmd', status: 'running', startedAt: 9_000 },
+      ],
+    }
+    const store = makeStore(snapshot)
+    const { container, unmount } = mount(
+      createElement(SubagentView, { sessionId: 'root', active: true, ctx: makeCtx(store) }),
+    )
+    const row = container.querySelector('button[aria-label*="unread cmd"]') as HTMLButtonElement
+    await act(async () => { row.click() })
+    // read:false → the pane explains the model has not read it (never the
+    // model's cursor, so there is nothing to steal yet).
+    expect(container.textContent).toContain('模型尚未读取该任务的输出')
+    unmount()
+  })
+
   it('stays compact and functional with many tasks', async () => {
     const many = Array.from({ length: 60 }, (_, index) => ({
       id: `bash-${index + 10}`,

tests/tasks-routes.spec.ts

@@ -1,17 +1,20 @@
 /**
- * Host route tests for the background-task API ('tasks.output' / 'tasks.kill'):
- * caller resolution from the requested session, the non-consuming peek
- * contract (capped, never reported), kill semantics, and the optional-service
- * downgrade when the deployment lacks the tasks registry.
+ * Host route tests for the background-task API ('tasks.output' / 'tasks.kill').
+ * 'tasks.output' REPLAYS the output the model has read so far from the owner
+ * session's event log (tool/call + tool/result pairs of task_output calls) —
+ * the model's cursor is never touched, so nothing is stolen and unread tasks
+ * report `read: false`. 'tasks.kill' uses the registry's stock kill, fenced
+ * by the owning session, with a 503 when the registry is absent.
  */
 import { describe, expect, it, vi } from 'vitest'
 import { buildTasksApi } from '../src/tasks-routes.ts'
 import { SidebarError } from '../src/wire.ts'
-import type { Context } from '../src/context-types.ts'
+import type { Context, SidebarSessionEvent } from '../src/context-types.ts'
 
-/** A context whose `get` serves only the tasks/agents faces. */
-function ctxWith(tasks: unknown, agents: unknown): Context {
+/** A context whose `get` serves only the tasks/agents faces, with a session store. */
+function ctxWith(sessions: unknown, tasks: unknown, agents: unknown): Context {
   return {
+    sessions,
     get: (key: string) => (key === 'tasks' ? tasks : key === 'agents' ? agents : undefined),
   } as unknown as Context
 }
@@ -19,49 +22,92 @@ function ctxWith(tasks: unknown, agents: unknown): Context {
 /** A stub live agent (the fence compares `id` only). */
 const agent = (id: string) => ({ id, session: { header: { cwd: '/p' } } })
 
-describe('tasks.output route', () => {
-  it('peeks the full output with the live caller of the requested session', () => {
-    const tasks = {
-      peek: vi.fn(() => ({ text: 'line1\nline2\n', snapshot: { status: 'running' } })),
-    }
-    const agents = { get: vi.fn((id: string) => agent(id)) }
-    const api = buildTasksApi(ctxWith(tasks, agents), 512 * 1024)!
-    const value = api.output({ sessionId: 's1', id: 'bash-1' })
+/** One task_output tool/call event. */
+function taskOutputCall(seq: number, callId: string, taskId: string): SidebarSessionEvent {
+  return { type: 'tool/call', seq, time: seq, data: { name: 'task_output', callId, arguments: JSON.stringify({ task_id: taskId }) } }
+}
 
-    expect(value).toEqual({ text: 'line1\nline2\n', truncated: false, status: 'running' })
-    // The caller is the live agent of the OWNING session, and the registry
-    // call is a peek (non-consuming by construction of the seam contract).
-    expect(agents.get).toHaveBeenCalledWith('s1')
-    expect(tasks.peek).toHaveBeenCalledWith('bash-1', agent('s1'))
+/** One tool/result event carrying the finalized text the model received. */
+function taskOutputResult(seq: number, callId: string, text: string, over: { isError?: boolean } = {}): SidebarSessionEvent {
+  return {
+    type: 'tool/result',
+    seq,
+    time: seq,
+    data: {
+      message: {
+        source: { kind: 'tool', callId },
+        content: [{
+          type: 'tool-result',
+          toolCallId: callId,
+          isError: over.isError === true,
+          content: [{ type: 'text', text }],
+        }],
+      },
+    },
+  }
+}
+
+/** The owner session with the given event log. */
+function session(events: SidebarSessionEvent[]): unknown {
+  return { header: { cwd: '/p' }, events }
+}
+
+describe('tasks.output route (event replay)', () => {
+  it('concatenates the task_output results the model read for the task, oldest first', () => {
+    const events = [
+      taskOutputCall(0, 'c1', 'bash-1'),
+      taskOutputResult(1, 'c1', 'line1\nline2\n[status: running]'),
+      taskOutputCall(2, 'c2', 'bash-1'),
+      taskOutputResult(3, 'c2', 'line3\n[status: completed, exit code: 0]'),
+      // Another task's reads are ignored.
+      taskOutputCall(4, 'c3', 'bash-2'),
+      taskOutputResult(5, 'c3', 'other task output'),
+    ]
+    const api = buildTasksApi(ctxWith({ get: () => session(events) }, undefined, undefined), 512 * 1024)
+    expect(api.output({ sessionId: 's1', id: 'bash-1' })).toEqual({
+      text: 'line1\nline2\n[status: running]\nline3\n[status: completed, exit code: 0]',
+      truncated: false,
+      read: true,
+    })
   })
 
-  it('carries the terminal detail and caps oversized output with the truncated flag', () => {
-    const tasks = {
-      peek: vi.fn(() => ({
-        text: 'x'.repeat(10_000),
-        snapshot: { status: 'completed', detail: 'exit code: 0' },
-      })),
-    }
-    const api = buildTasksApi(ctxWith(tasks, undefined), 100)!
-    const value = api.output({ sessionId: 's1', id: 'bash-1' })
+  it('skips the controller\'s "(no new output)" deltas and error results', () => {
+    const events = [
+      taskOutputCall(0, 'c1', 'bash-1'),
+      taskOutputResult(1, 'c1', 'real output\n[status: running]'),
+      taskOutputCall(2, 'c2', 'bash-1'),
+      taskOutputResult(3, 'c2', '(no new output)\n[status: running]'),
+      taskOutputCall(4, 'c3', 'bash-1'),
+      taskOutputResult(5, 'c3', 'boom', { isError: true }),
+    ]
+    const api = buildTasksApi(ctxWith({ get: () => session(events) }, undefined, undefined), 512 * 1024)
+    expect(api.output({ sessionId: 's1', id: 'bash-1' })).toEqual({
+      text: 'real output\n[status: running]',
+      truncated: false,
+      read: true,
+    })
+  })
 
+  it('reports read:false until the model reads the task (no registry call at all)', () => {
+    const events = [taskOutputCall(0, 'c1', 'bash-2')]
+    const tasks = { kill: vi.fn() }
+    const api = buildTasksApi(ctxWith({ get: () => session(events) }, tasks, undefined), 100)
+    expect(api.output({ sessionId: 's1', id: 'bash-1' })).toEqual({ text: '', truncated: false, read: false })
+    // The replay never touches the registry — the model's cursor is safe by construction.
+    expect(tasks.kill).not.toHaveBeenCalled()
+  })
+
+  it('caps oversized replays with the truncated flag', () => {
+    const events = [taskOutputCall(0, 'c1', 'bash-1'), taskOutputResult(1, 'c1', 'x'.repeat(10_000))]
+    const api = buildTasksApi(ctxWith({ get: () => session(events) }, undefined, undefined), 100)
+    const value = api.output({ sessionId: 's1', id: 'bash-1' })
     expect(value.text).toBe('x'.repeat(100))
     expect(value.truncated).toBe(true)
-    expect(value.status).toBe('completed')
-    expect(value.detail).toBe('exit code: 0')
-  })
-
-  it('maps registry refusals to a 404 task-error (unknown/foreign ids stay indistinguishable)', () => {
-    const tasks = { peek: vi.fn(() => { throw new Error('task bash-9 belongs to another session') }) }
-    const api = buildTasksApi(ctxWith(tasks, {}), 100)!
-    expect(() => api.output({ sessionId: 's1', id: 'bash-9' })).toThrowError(
-      expect.objectContaining<Partial<SidebarError>>({ code: 'task-error', status: 404 }),
-    )
+    expect(value.read).toBe(true)
   })
 
   it('rejects a missing sessionId or id as bad-request', () => {
-    const tasks = { peek: vi.fn() }
-    const api = buildTasksApi(ctxWith(tasks, {}), 100)!
+    const api = buildTasksApi(ctxWith({ get: () => undefined }, undefined, undefined), 100)
     expect(() => api.output({ id: 'bash-1' })).toThrowError(expect.objectContaining<Partial<SidebarError>>({ code: 'bad-request' }))
     expect(() => api.output({ sessionId: 's1' })).toThrowError(expect.objectContaining<Partial<SidebarError>>({ code: 'bad-request' }))
   })
@@ -71,7 +117,7 @@ describe('tasks.kill route', () => {
   it('kills with the forwarded reason and the live caller', () => {
     const tasks = { kill: vi.fn(() => 'requested' as const) }
     const agents = { get: vi.fn((id: string) => agent(id)) }
-    const api = buildTasksApi(ctxWith(tasks, agents), 100)!
+    const api = buildTasksApi(ctxWith({ get: () => undefined }, tasks, agents), 100)
     expect(api.kill({ sessionId: 's1', id: 'bash-1', reason: 'user pressed stop' }))
       .toEqual({ ok: true, outcome: 'requested' })
     expect(tasks.kill).toHaveBeenCalledWith('bash-1', agent('s1'), 'user pressed stop')
@@ -79,29 +125,24 @@ describe('tasks.kill route', () => {
 
   it('defaults the reason when none is supplied', () => {
     const tasks = { kill: vi.fn(() => 'already-finished' as const) }
-    const api = buildTasksApi(ctxWith(tasks, undefined), 100)!
+    const api = buildTasksApi(ctxWith({ get: () => undefined }, tasks, undefined), 100)
     expect(api.kill({ sessionId: 's1', id: 'bash-1' })).toEqual({ ok: true, outcome: 'already-finished' })
     expect(tasks.kill).toHaveBeenCalledWith('bash-1', undefined, 'user requested via sidebar')
   })
 
   it('maps registry refusals to a 404 task-error', () => {
     const tasks = { kill: vi.fn(() => { throw new Error('unknown task bash-9') }) }
-    const api = buildTasksApi(ctxWith(tasks, {}), 100)!
+    const api = buildTasksApi(ctxWith({ get: () => undefined }, tasks, undefined), 100)
     expect(() => api.kill({ sessionId: 's1', id: 'bash-9' })).toThrowError(
       expect.objectContaining<Partial<SidebarError>>({ code: 'task-error', status: 404 }),
     )
   })
-})
 
-describe('optional-service downgrade', () => {
-  it('returns undefined (the caller maps to a 503) when ctx.tasks is absent', () => {
-    expect(buildTasksApi(ctxWith(undefined, {}), 100)).toBeUndefined()
-  })
-
-  it('resolves the caller as undefined when the agents registry is absent', () => {
-    const tasks = { peek: vi.fn(() => ({ text: '', snapshot: { status: 'running' } })), kill: vi.fn(() => 'requested' as const) }
-    const api = buildTasksApi(ctxWith(tasks, undefined), 100)!
-    api.output({ sessionId: 's1', id: 'bash-1' })
-    expect(tasks.peek).toHaveBeenCalledWith('bash-1', undefined)
+  it('degrades to a 503 when the tasks registry is absent (output keeps working)', () => {
+    const api = buildTasksApi(ctxWith({ get: () => session([]) }, undefined, undefined), 100)
+    expect(() => api.kill({ sessionId: 's1', id: 'bash-1' })).toThrowError(
+      expect.objectContaining<Partial<SidebarError>>({ code: 'task-error', status: 503 }),
+    )
+    expect(api.output({ sessionId: 's1', id: 'bash-1' })).toEqual({ text: '', truncated: false, read: false })
   })
 })