feat(memory,conversation): 记忆富化/证据包、时间线幂等字段与对话分段全链路

数据库
- 新增迁移 0003：timeline_events.memory_source_id 外键 → memory_sources，便于按 ingest 源做时间线幂等

后端 - 记忆
- 新增 ingest 后 LLM 富化（摘要/事实/时间线），可配置开关与最大字符数
- 新增证据包组装：合并 chunk、摘要、事实、时间线、故事等检索结果；支持空 query 时是否仍带 rolling 等开关
- repo/retriever/service/router/schemas/summarizer/timeline/extractor 等扩展；文档 memory-retrieval.md 更新

后端 - 对话 WS
- 增加 PING/PONG；分段 ASR 日志与空音频处理；转写失败与「无助手回复」错误提示更明确
- 助手多段回复持久化使用统一分隔符，与分段逻辑一致

后端 - Agent
- reply_limits：按 [SPLIT] 与段落拆段，并保证非空 fallback，供 WS 与 TTS 多段下发

后端 - 回忆录任务
- transcript ingest 记录 source_id；任务成功结?

app-expo/tests/core/audio/audio-focus.test.ts

@@ -1,7 +1,12 @@
+/* eslint-disable import/first */
+
 const mockSetAudioModeAsync = jest.fn().mockResolvedValue(undefined);
+const mockSetIsAudioActiveAsync = jest.fn().mockResolvedValue(undefined);
 
 jest.mock('expo-audio', () => ({
   setAudioModeAsync: (...args: unknown[]) => mockSetAudioModeAsync(...args),
+  setIsAudioActiveAsync: (...args: unknown[]) =>
+    mockSetIsAudioActiveAsync(...args),
 }));
 
 import { audioFocus } from '@/core/audio/audio-focus';
@@ -9,8 +14,10 @@ import { audioFocus } from '@/core/audio/audio-focus';
 describe('audioFocus', () => {
   beforeEach(async () => {
     mockSetAudioModeAsync.mockClear();
+    mockSetIsAudioActiveAsync.mockClear();
     await audioFocus.release();
     mockSetAudioModeAsync.mockClear();
+    mockSetIsAudioActiveAsync.mockClear();
   });
 
   test('acquires focus for recording', async () => {
@@ -50,6 +57,26 @@ describe('audioFocus', () => {
     expect(audioFocus.isPlaying()).toBe(false);
   });
 
+  test('releaseIfOwnedBy does not clear another owner', async () => {
+    await audioFocus.acquireForRecording();
+
+    await audioFocus.releaseIfOwnedBy('player');
+    expect(audioFocus.isRecording()).toBe(true);
+    expect(audioFocus.getCurrentOwner()).toBe('recorder');
+
+    await audioFocus.releaseIfOwnedBy('recorder');
+    expect(audioFocus.getCurrentOwner()).toBeNull();
+  });
+
+  test('release deactivates the native audio session', async () => {
+    await audioFocus.acquireForPlayback();
+
+    await audioFocus.release();
+
+    expect(mockSetIsAudioActiveAsync).toHaveBeenCalledWith(false);
+    expect(audioFocus.getCurrentOwner()).toBeNull();
+  });
+
   test('notifies listeners on owner change', async () => {
     const listener = jest.fn();
     const unsub = audioFocus.onOwnerChange(listener);