feat(api): 访谈路径轻量门控、Memoir Phase1 批处理与叙事/记忆管线加固

- 新增 utterance_substance：短时/应答/元话语可跳过记忆检索、阶段 LLM 与资料抽取 LLM；可配置
- 输入归一化：LLM 模式默认仅语音/ASR；配置项写入 .env.example
- Memoir Phase1：可选 batch LLM 一次性抽取+分类（失败回退逐段）；Extraction 空槽位时阶段与 current_stage 对齐，prompt 约束收紧
- 叙事与忠实度：narrative_safety、证据重叠/场合锚点、标题 slots 与履历短语 grounded；fidelity 解析失败 fail-open 可配置
- 章节管线：锁 TTL 上调、锁竞争 Celery 重试、Phase2 immediate singleflight 等；story_pipeline_sync / chapter_compose / memoir_tasks 联动
- Memory：compaction / repo / summarizer / evidence 小修；事实 FTS 未命中是否回退最近事实可配置
- 新增 memoir_pipeline_trace；补充 memoir_reliability 文档与多项回归/门控测试

api/tests/test_recompose_retry_policy.py

@@ -0,0 +1,87 @@
+"""recompose_chapter：锁竞争时 retry（可配置）。"""
+
+from __future__ import annotations
+
+from contextlib import contextmanager
+from unittest.mock import MagicMock, patch
+
+import pytest
+from celery.exceptions import Retry
+
+from app.core.config import settings
+from app.tasks.chapter_compose_tasks import recompose_chapter
+
+
+class _FakeSyncDb:
+    """模拟 `with get_sync_db() as session`。"""
+
+    def __init__(self, session: MagicMock) -> None:
+        self._session = session
+
+    def __enter__(self) -> MagicMock:
+        return self._session
+
+    def __exit__(self, *exc: object) -> bool:
+        return False
+
+
+def test_recompose_retries_when_lock_busy_and_flag_on(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    monkeypatch.setattr(
+        settings, "memoir_recompose_retry_on_lock_contention", True, raising=False
+    )
+    session = MagicMock()
+    ch = MagicMock()
+    ch.markdown_compose_dirty = True
+    ch.user_id = "user-1"
+    ch.category = "childhood"
+    session.get.return_value = ch
+
+    with (
+        patch(
+            "app.tasks.chapter_compose_tasks.get_sync_db",
+            return_value=_FakeSyncDb(session),
+        ),
+        patch(
+            "app.tasks.chapter_compose_tasks.acquire_chapter_pipeline_lock",
+            return_value=None,
+        ),
+    ):
+        with patch.object(
+            recompose_chapter, "retry", side_effect=Retry("lock_busy")
+        ) as mock_retry:
+            with pytest.raises(Retry):
+                recompose_chapter.run("chapter-1")
+        mock_retry.assert_called_once()
+        _, kwargs = mock_retry.call_args
+        assert "countdown" in kwargs
+
+
+def test_recompose_skips_when_lock_busy_and_flag_off(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    monkeypatch.setattr(
+        settings, "memoir_recompose_retry_on_lock_contention", False, raising=False
+    )
+    session = MagicMock()
+    ch = MagicMock()
+    ch.markdown_compose_dirty = True
+    ch.user_id = "user-1"
+    ch.category = "childhood"
+    session.get.return_value = ch
+
+    with (
+        patch(
+            "app.tasks.chapter_compose_tasks.get_sync_db",
+            return_value=_FakeSyncDb(session),
+        ),
+        patch(
+            "app.tasks.chapter_compose_tasks.acquire_chapter_pipeline_lock",
+            return_value=None,
+        ),
+    ):
+        with patch.object(recompose_chapter, "retry") as mock_retry:
+            out = recompose_chapter.run("chapter-1")
+        assert out == {"status": "skip_lock_contention"}
+        mock_retry.assert_not_called()