feat: M3 — 伏笔账本 + 节奏引擎 + 大纲（含并发记账 bugfix）

- 伏笔账本：纯函数状态机(OPEN/PARTIAL/CLOSED/OVERDUE) + ForeshadowLedger repo；验收后到期扫描(BackgroundTask 自建 session 置 OVERDUE)；登记/状态变更端点 - 节奏 + 三审齐：foreshadow-analyst + pace-checker 并入 LangGraph 并行审(REVIEW_SPECS)，collect 分列落 chapter_reviews(conflicts/foreshadow_sug/pace)，review SSE 加 foreshadow/pace 事件 - 大纲：outliner Agent 产 OutlineResult(含 foreshadow_windows)，POST /outline 逐章 upsert outline 表；GET /foreshadow?status= 看板 - 前端：伏笔四泳道看板(OVERDUE 琥珀) + 大纲编辑器(窗口徽标) + 节奏节拍图(▁▃▅) + 审稿页消费 foreshadow/pace SSE - bugfix(T3.8)：并行三审共用请求 session 记账触发 'Session is already flushing' → foreshadow/pace 静默丢失；SqlAlchemyLedgerSink.record 改 add-only(靠端点/事务 commit)，加并发回归测试 - M3 E2E：真实 DB + mock 网关零 token 走通埋设→进展→验收后扫描 OVERDUE→看板 + 大纲含窗口 + 三审齐 SSE/留痕；E2E 暴露并钉住上述 bug - 门禁绿：mypy 111 / pytest 228(0 xfailed) / alembic 无漂移；前端 gen:api/lint/tsc/vitest 69/build
2026-06-18 14:21:17 +02:00
parent 68f194a043
commit 5fb7bfb1de
74 changed files with 6529 additions and 126 deletions
--- a/apps/api/ww_api/main.py
+++ b/apps/api/ww_api/main.py
@@ -12,7 +12,14 @@ from ww_shared import AppError, ErrorBody, ErrorEnvelope

 from ww_api.logging_config import configure_logging, get_logger
 from ww_api.middleware import request_id_middleware
-from ww_api.routers import health, jobs, projects, settings_providers
+from ww_api.routers import (
+    foreshadow,
+    health,
+    jobs,
+    outline,
+    projects,
+    settings_providers,
+)
 from ww_api.services.project_deps import seed_stub_user

 configure_logging()
@@ -48,6 +55,8 @@ def create_app() -> FastAPI:
    app.include_router(health.router)
    app.include_router(jobs.router)
    app.include_router(projects.router)
+    app.include_router(foreshadow.router)
+    app.include_router(outline.router)
    app.include_router(settings_providers.router)
    return app

--- a/apps/api/ww_api/routers/foreshadow.py
+++ b/apps/api/ww_api/routers/foreshadow.py
@@ -0,0 +1,159 @@
+"""伏笔登记 / 状态变更端点（C3 扩 / ARCH §6.2, §7.2；不变量 #3）。
+
+- POST  /projects/:id/foreshadow          作者显式登记一条伏笔（status=OPEN）。
+- PATCH /projects/:id/foreshadow/:code     状态机转移 和/或 追加进展。
+
+登记/改状态是**作者显式动作**（不变量 #3：伏笔入库不经 AI 静默写库；验收后到期扫描
+是确定性纯函数置位，见 `services/foreshadow_scan.py`）。
+
+提交边界：`ForeshadowLedgerRepo` 写方法只 `flush()`，端点写后 `await session.commit()`。
+
+**T3.5 续接点**：本 router 是 foreshadow 端点的归属处。T3.5 的看板查询
+`GET /projects/:id/foreshadow?status=` 直接加到本 router（调 `repo.list_by_status`）；
+大纲 `POST /projects/:id/outline` 与伏笔无关，建议落独立 `routers/outline.py`
+（或 projects router），不混进本文件。
+"""
+
+from __future__ import annotations
+
+import uuid
+from typing import Annotated
+
+from fastapi import APIRouter, Depends, Request
+from sqlalchemy.exc import IntegrityError
+from sqlalchemy.ext.asyncio import AsyncSession
+from ww_core.domain import ForeshadowLedgerRepo, ForeshadowLedgerView
+from ww_core.domain.foreshadow_state import ForeshadowStatus, InvalidTransition
+from ww_db import get_session
+from ww_shared import AppError, ErrorCode
+
+from ww_api.logging_config import get_logger
+from ww_api.schemas.foreshadow import (
+    ForeshadowBoardResponse,
+    ForeshadowRegisterRequest,
+    ForeshadowTransitionRequest,
+    ForeshadowView,
+)
+from ww_api.services.project_deps import get_foreshadow_repo
+
+log = get_logger("ww.api.foreshadow")
+
+router = APIRouter(prefix="/projects", tags=["foreshadow"])
+
+ForeshadowRepoDep = Annotated[ForeshadowLedgerRepo, Depends(get_foreshadow_repo)]
+SessionDep = Annotated[AsyncSession, Depends(get_session)]
+
+
+def _to_view(v: ForeshadowLedgerView) -> ForeshadowView:
+    # ForeshadowLedgerView 与 ForeshadowView 字段同名，逐字段映射（snake_case 契约）。
+    return ForeshadowView.model_validate(v, from_attributes=True)
+
+
+@router.post("/{project_id}/foreshadow", status_code=201)
+async def register_foreshadow(
+    project_id: uuid.UUID,
+    body: ForeshadowRegisterRequest,
+    request: Request,
+    repo: ForeshadowRepoDep,
+    session: SessionDep,
+) -> ForeshadowView:
+    """登记一条伏笔（status=OPEN）。重复 `code` → DB 唯一约束冲突 → VALIDATION 信封。"""
+    request_id = getattr(request.state, "request_id", None)
+    try:
+        view = await repo.register(
+            project_id,
+            code=body.code,
+            title=body.title,
+            planted_at=body.planted_at,
+            content=body.content,
+            expected_close_from=body.expected_close_from,
+            expected_close_to=body.expected_close_to,
+            importance=body.importance,
+        )
+        await session.commit()
+    except IntegrityError as exc:
+        # `(project_id, code)` 唯一约束冲突（register 仅 INSERT、不 upsert，见 foreshadow_repo）。
+        await session.rollback()
+        raise AppError(
+            ErrorCode.VALIDATION,
+            f"伏笔代号已存在：{body.code}",
+            {"field": "code", "code": body.code, "reason": "duplicate"},
+        ) from exc
+    log.info(
+        "foreshadow_registered",
+        project_id=str(project_id),
+        request_id=request_id,
+        code=body.code,
+    )
+    return _to_view(view)
+
+
+@router.get("/{project_id}/foreshadow")
+async def list_foreshadow(
+    project_id: uuid.UUID,
+    repo: ForeshadowRepoDep,
+    status: str | None = None,
+) -> ForeshadowBoardResponse:
+    """伏笔看板：按 `status` 过滤（缺省=全部），按 code 升序。
+
+    `status` 非法（不在 OPEN/PARTIAL/CLOSED/OVERDUE）→ VALIDATION 信封。四泳道前端
+    据 `status` 分组；OVERDUE 泳道 + 逾期标记用 `expected_close_to`（看板字段已齐）。
+    """
+    if status is not None and status not in {s.value for s in ForeshadowStatus}:
+        raise AppError(
+            ErrorCode.VALIDATION,
+            f"非法状态过滤：{status}",
+            {"field": "status", "reason": "invalid_status"},
+        )
+    views = await repo.list_by_status(project_id, status)
+    return ForeshadowBoardResponse(foreshadow=[_to_view(v) for v in views])
+
+
+@router.patch("/{project_id}/foreshadow/{code}")
+async def update_foreshadow(
+    project_id: uuid.UUID,
+    code: str,
+    body: ForeshadowTransitionRequest,
+    request: Request,
+    repo: ForeshadowRepoDep,
+    session: SessionDep,
+) -> ForeshadowView:
+    """状态机转移 和/或 追加进展。非法转移 → VALIDATION 信封；不存在 → NOT_FOUND。
+
+    `to_status` 与 `progress_entry` 皆可选；两者都缺 → VALIDATION（无操作）。先转移、后追加。
+    """
+    request_id = getattr(request.state, "request_id", None)
+    if body.to_status is None and body.progress_entry is None:
+        raise AppError(
+            ErrorCode.VALIDATION,
+            "至少提供 `to_status` 或 `progress_entry` 之一",
+            {"reason": "empty_update"},
+        )
+
+    view: ForeshadowLedgerView
+    try:
+        if body.to_status is not None:
+            view = await repo.transition(project_id, code, to_status=body.to_status)
+        if body.progress_entry is not None:
+            view = await repo.record_progress(project_id, code, entry=body.progress_entry)
+        await session.commit()
+    except InvalidTransition as exc:
+        await session.rollback()
+        raise AppError(
+            ErrorCode.VALIDATION,
+            str(exc),
+            {"field": "to_status", "code": code, "reason": "invalid_transition"},
+        ) from exc
+    except LookupError as exc:
+        await session.rollback()
+        raise AppError(ErrorCode.NOT_FOUND, f"foreshadow not found: {code}") from exc
+
+    log.info(
+        "foreshadow_updated",
+        project_id=str(project_id),
+        request_id=request_id,
+        code=code,
+        to_status=body.to_status,
+        has_progress=body.progress_entry is not None,
+    )
+    return _to_view(view)
--- a/apps/api/ww_api/routers/outline.py
+++ b/apps/api/ww_api/routers/outline.py
@@ -0,0 +1,135 @@
+"""大纲生成端点（C3 扩 / ARCH §5.4 outliner / §7.2 POST /outline；不变量 #2/#3）。
+
+POST /projects/:id/outline：作者显式发起大纲生成 + 持久化。
+
+流程：组确定性上下文（设定 + 已登记伏笔 + 人物 + 世界观）→ `run_outline`（analyst 网关，
+结构化 `OutlineResult`）→ 逐章 upsert `outline` 表 → 端点末尾一次 `commit()`。
+
+提交边界：网关 ledger 只 flush（run_outline 产 1 条 usage）、`OutlineWriteRepo.upsert_chapter`
+只 flush → 端点末尾 `await session.commit()`（否则 usage_ledger + outline 行静默丢失，见 gotcha）。
+
+不变量 #2：经 `build_gateway_for_tier(..., "analyst")` 注入；outliner_spec 只声明档位不传 model。
+不变量 #3：outliner `writes=["outline"]` 经此**作者发起**端点落地，非 AI 静默写其它表；
+run_outline 节点本身只读不写库。无凭据 → `LLM_UNAVAILABLE`（友好提示，仿 draft/review）。
+"""
+
+from __future__ import annotations
+
+import uuid
+from typing import Annotated
+
+from fastapi import APIRouter, Depends, Request
+from sqlalchemy.ext.asyncio import AsyncSession
+from ww_agents import outliner_spec
+from ww_core.domain import ForeshadowLedgerRepo, OutlineWriteRepo, ProjectRepo
+from ww_core.domain.repositories import MemoryRepos
+from ww_core.orchestrator import run_outline
+from ww_db import get_session
+from ww_llm_gateway import Gateway
+from ww_shared import AppError, ErrorCode
+
+from ww_api.logging_config import get_logger
+from ww_api.schemas.outline import (
+    ForeshadowWindowView,
+    OutlineChapterView,
+    OutlineGenerateRequest,
+    OutlineResponse,
+)
+from ww_api.services.credentials import STUB_OWNER_ID
+from ww_api.services.outline_context import build_outline_context
+from ww_api.services.project_deps import (
+    get_foreshadow_repo,
+    get_memory_repos,
+    get_outline_gateway,
+    get_outline_write_repo,
+    get_project_repo,
+)
+
+log = get_logger("ww.api.outline")
+
+router = APIRouter(prefix="/projects", tags=["outline"])
+
+ProjectRepoDep = Annotated[ProjectRepo, Depends(get_project_repo)]
+ForeshadowRepoDep = Annotated[ForeshadowLedgerRepo, Depends(get_foreshadow_repo)]
+MemoryReposDep = Annotated[MemoryRepos, Depends(get_memory_repos)]
+OutlineWriteRepoDep = Annotated[OutlineWriteRepo, Depends(get_outline_write_repo)]
+OutlineGatewayDep = Annotated[Gateway, Depends(get_outline_gateway)]
+SessionDep = Annotated[AsyncSession, Depends(get_session)]
+
+
+@router.post("/{project_id}/outline")
+async def generate_outline(
+    project_id: uuid.UUID,
+    body: OutlineGenerateRequest,
+    request: Request,
+    project_repo: ProjectRepoDep,
+    foreshadow_repo: ForeshadowRepoDep,
+    memory_repos: MemoryReposDep,
+    outline_repo: OutlineWriteRepoDep,
+    gateway: OutlineGatewayDep,
+    session: SessionDep,
+) -> OutlineResponse:
+    """生成大纲并逐章持久化。无凭据 → LLM_UNAVAILABLE；项目不存在 → NOT_FOUND。"""
+    request_id = getattr(request.state, "request_id", None)
+
+    project = await project_repo.get(STUB_OWNER_ID, project_id)
+    if project is None:
+        raise AppError(ErrorCode.NOT_FOUND, f"project not found: {project_id}")
+
+    foreshadow = await foreshadow_repo.list_by_status(project_id, None)
+    characters = await memory_repos.character.list_for_project(project_id)
+    world_entities = await memory_repos.world_entity.list_for_project(project_id)
+    context = build_outline_context(
+        project=project,
+        foreshadow=foreshadow,
+        characters=characters,
+        world_entities=world_entities,
+    )
+
+    log.info(
+        "outline_generate_start",
+        project_id=str(project_id),
+        request_id=request_id,
+        volume=body.volume,
+        context_len=len(context),
+        foreshadow_count=len(foreshadow),
+    )
+
+    # run_outline 产结构化大纲（analyst 网关；网关失败上抛，无凭据 → LLM_UNAVAILABLE）。
+    result = await run_outline(
+        outliner_spec,
+        context=context,
+        gateway=gateway,
+        user_id=STUB_OWNER_ID,
+        project_id=project_id,
+    )
+
+    chapters: list[OutlineChapterView] = []
+    for chapter in result.chapters:
+        windows = [w.model_dump() for w in chapter.foreshadow_windows]
+        await outline_repo.upsert_chapter(
+            project_id,
+            volume=body.volume,
+            chapter_no=chapter.no,
+            beats=chapter.beats,
+            foreshadow_windows=windows,
+        )
+        chapters.append(
+            OutlineChapterView(
+                no=chapter.no,
+                volume=body.volume,
+                beats=list(chapter.beats),
+                foreshadow_windows=[ForeshadowWindowView(**w) for w in windows],
+            )
+        )
+
+    # 提交边界：网关 ledger + outline upsert 均只 flush → 端点末尾一次 commit。
+    await session.commit()
+
+    log.info(
+        "outline_generate_done",
+        project_id=str(project_id),
+        request_id=request_id,
+        chapter_count=len(chapters),
+    )
+    return OutlineResponse(chapters=chapters)
--- a/apps/api/ww_api/routers/projects.py
+++ b/apps/api/ww_api/routers/projects.py
@@ -17,7 +17,7 @@ import uuid
 from collections.abc import AsyncIterator
 from typing import Annotated

-from fastapi import APIRouter, Depends, Request
+from fastapi import APIRouter, BackgroundTasks, Depends, Request
 from fastapi.responses import StreamingResponse
 from sqlalchemy.ext.asyncio import AsyncSession
 from ww_core.domain.chapter_repo import ChapterRepo
@@ -59,6 +59,7 @@ from ww_api.services.accept_service import (
 )
 from ww_api.services.credentials import STUB_OWNER_ID
 from ww_api.services.digest_extraction import extract_digest_facts
+from ww_api.services.foreshadow_scan import SessionFactory, run_overdue_scan
 from ww_api.services.project_deps import (
    get_chapter_repo,
    get_digest_append_repo,
@@ -67,6 +68,7 @@ from ww_api.services.project_deps import (
    get_project_repo,
    get_review_gateway,
    get_review_repo,
+    get_session_factory,
    get_writer_gateway,
 )

@@ -302,14 +304,23 @@ async def accept_chapter(
    chapter_no: int,
    body: AcceptRequest,
    request: Request,
+    background_tasks: BackgroundTasks,
    chapter_repo: ChapterRepoDep,
    digest_repo: DigestRepoDep,
    review_repo: ReviewRepoDep,
    gateway: DigestGatewayDep,
    session: Annotated[AsyncSession, Depends(get_session)],
+    session_factory: Annotated[SessionFactory, Depends(get_session_factory)],
 ) -> AcceptResponse:
    """验收事务 + 冲突 gate（§5.5）：gate（事务前）→ 终稿提炼 digest（事务外，R2）→
-    单原子事务（晋升 + digest + 裁决留痕）→ 一次 commit。
+    单原子事务（晋升 + digest + 裁决留痕）→ 一次 commit → 登记**验收后伏笔到期扫描**
+    BackgroundTask（M3-b/d，§6.2）。
+
+    到期扫描接 §5.5 步骤 3 的 `TODO(M3)` 占位：验收提交成功**后**，把
+    `current_ch > expected_close_to AND status≠CLOSED` 的伏笔确定性置 OVERDUE。
+    伏笔登记/回收（PARTIAL/CLOSED）的「采纳建议」经作者经 foreshadow 端点显式确认，
+    不在验收事务里 AI 静默改库（不变量 #3）。**§7.4 持久性局限**：BackgroundTask 进程内
+    跑、重启丢失——原型可接受（见 `services/foreshadow_scan.py`，不引入 jobs 表）。
    """
    request_id = getattr(request.state, "request_id", None)
    # R3：审稿真相从领域表重读（最近一条 chapter_reviews），不依赖 checkpoint。
@@ -350,6 +361,17 @@ async def accept_chapter(
        latest_review=latest_review,
        decisions=body.decisions,
    )
+
+    # 验收**提交成功后**登记伏笔到期扫描 BackgroundTask（M3-b/d）。current_chapter=刚验收章号；
+    # 任务在请求 session 关闭后跑，故 run_overdue_scan 自建新 session 并 commit（§7.4 局限可接受）。
+    background_tasks.add_task(
+        run_overdue_scan,
+        session_factory,
+        project_id=project_id,
+        chapter_no=chapter_no,
+        request_id=request_id,
+    )
+
    return AcceptResponse(
        project_id=project_id,
        chapter_no=chapter_no,
--- a/apps/api/ww_api/schemas/foreshadow.py
+++ b/apps/api/ww_api/schemas/foreshadow.py
@@ -0,0 +1,66 @@
+"""伏笔登记 / 状态变更端点的请求/响应 schema（C3 扩 / ARCH §6.2, §7.2）。
+
+snake_case；前端经 OpenAPI 生成 TS 类型消费。改字段 → 前端必须 `pnpm gen:api`。
+登记是**作者显式动作**（不变量 #3：伏笔入库不经 AI 静默写库），到期扫描是验收后的
+确定性纯函数置位（M3-d），二者都不在审稿/写章流水线里。
+"""
+
+from __future__ import annotations
+
+from typing import Any
+
+from pydantic import BaseModel, Field
+
+
+class ForeshadowRegisterRequest(BaseModel):
+    """POST /projects/:id/foreshadow：作者显式登记一条伏笔（status 落 OPEN）。"""
+
+    code: str = Field(min_length=1, description="伏笔代号，`(project_id, code)` 唯一")
+    title: str = Field(min_length=1, description="伏笔标题/一句话描述")
+    planted_at: int | None = Field(default=None, description="埋设章号")
+    content: str | None = Field(default=None, description="伏笔正文/线索")
+    expected_close_from: int | None = Field(default=None, description="预期回收窗口起始章")
+    expected_close_to: int | None = Field(
+        default=None, description="预期回收窗口结束章（到期判据用）"
+    )
+    importance: str | None = Field(default=None, description="重要度（自由文本，看板用）")
+
+
+class ForeshadowTransitionRequest(BaseModel):
+    """PATCH /projects/:id/foreshadow/:code：状态机转移 和/或 追加一条进展。
+
+    两字段皆可选：`to_status` 走状态机（非法 → VALIDATION 信封）；`progress_entry`
+    append-only 追加到 progress JSONB。二者可同时给（先转移、后追加进展）。
+    """
+
+    to_status: str | None = Field(
+        default=None, description="目标状态（OPEN/PARTIAL/CLOSED/OVERDUE）"
+    )
+    progress_entry: dict[str, Any] | None = Field(
+        default=None, description="追加一条进展记录（append-only，不覆盖历史）"
+    )
+
+
+class ForeshadowView(BaseModel):
+    """伏笔账本视图（登记/状态变更/看板共用；snake_case）。形对齐 `ForeshadowLedgerView`。"""
+
+    code: str
+    title: str
+    status: str
+    planted_at: int | None = None
+    content: str | None = None
+    expected_close_from: int | None = None
+    expected_close_to: int | None = None
+    importance: str | None = None
+    links: list[dict[str, Any]] = Field(default_factory=list)
+    progress: list[dict[str, Any]] = Field(default_factory=list)
+
+
+class ForeshadowBoardResponse(BaseModel):
+    """GET /projects/:id/foreshadow?status=：伏笔看板（四泳道 + OVERDUE 字段齐）。
+
+    `status` 缺省返回全部；按 `code` 升序（repo `list_by_status` 已排序）。前端按
+    `status` 分四泳道（OPEN/PARTIAL/CLOSED/OVERDUE），用 `expected_close_to` 标逾期。
+    """
+
+    foreshadow: list[ForeshadowView] = Field(default_factory=list)
--- a/apps/api/ww_api/schemas/outline.py
+++ b/apps/api/ww_api/schemas/outline.py
@@ -0,0 +1,43 @@
+"""大纲生成端点的请求/响应 schema（C3 扩 / ARCH §5.4, §7.2）。
+
+snake_case；前端经 OpenAPI 生成 TS 类型消费（改字段 → 前端 `pnpm gen:api`）。
+大纲生成是**作者显式动作**（不变量 #3：outliner `writes=["outline"]` 声明经此端点落地，
+非 AI 静默写其它表）。窗口字段供前端 T3.6 渲染伏笔窗口徽标。
+"""
+
+from __future__ import annotations
+
+from pydantic import BaseModel, Field
+
+
+class OutlineGenerateRequest(BaseModel):
+    """POST /projects/:id/outline：触发大纲生成 + 持久化。
+
+    M3 简单分卷：`volume` 缺省=1（schema 无逐章卷号；本端点把整批章节落到同一卷）。
+    """
+
+    volume: int = Field(default=1, ge=1, description="本批大纲所属卷号（M3 默认全卷 1）")
+
+
+class ForeshadowWindowView(BaseModel):
+    """单章关联的伏笔回收窗口（snake_case；形对齐 `ww_agents.ForeshadowWindow`）。"""
+
+    code: str
+    plant_chapter: int | None = None
+    expected_close_from: int | None = None
+    expected_close_to: int | None = None
+
+
+class OutlineChapterView(BaseModel):
+    """单章大纲视图：章号 + 卷 + 节拍 + 伏笔窗口。"""
+
+    no: int
+    volume: int
+    beats: list[str] = Field(default_factory=list)
+    foreshadow_windows: list[ForeshadowWindowView] = Field(default_factory=list)
+
+
+class OutlineResponse(BaseModel):
+    """大纲生成响应：逐章已持久化的大纲（含窗口，供前端 T3.6）。"""
+
+    chapters: list[OutlineChapterView] = Field(default_factory=list)
--- a/apps/api/ww_api/services/accept_service.py
+++ b/apps/api/ww_api/services/accept_service.py
@@ -114,9 +114,11 @@ async def run_accept_transaction(
        )
        review_id = updated.id

-    # 步骤 3（占位）：人物 latest_state / 伏笔状态更新——M3 才正式接伏笔表，
-    # 这里按 §5.5 步骤 3 留占位，不引入 M3 表逻辑（避免越界写未就绪的状态机）。
-    # TODO(M3): 按裁决应用 latest_state 变更 + 伏笔登记/到期扫描（§6.2）。
+    # 步骤 3：伏笔到期扫描——验收提交**后**经端点登记的 BackgroundTask 跑（M3-b/d，
+    # `services/foreshadow_scan.run_overdue_scan`：current_ch > expected_close_to 且未 CLOSED
+    # → 置 OVERDUE，确定性纯函数非 AI，不变量 #3）。放在事务外/提交后是因为它是验收**结果**
+    # 的副作用、且自建独立 session（请求 session 此时已关闭）。
+    # 人物 latest_state 更新仍留后续（M4+）：本事务只落晋升 + digest + 裁决留痕。

    await session.commit()  # type: ignore[attr-defined]  # AsyncSession.commit()（fake 同形）

--- a/apps/api/ww_api/services/foreshadow_scan.py
+++ b/apps/api/ww_api/services/foreshadow_scan.py
@@ -0,0 +1,90 @@
+"""验收后伏笔到期扫描（M3-b/d；ARCH §6.2, §7.4，不变量 #3）。
+
+接 §5.5 验收事务后的 `TODO(M3)` 占位：验收**提交成功后**触发一次伏笔到期扫描，把
+`current_ch > expected_close_to AND status≠CLOSED` 的伏笔确定性置 `OVERDUE`（M3-d 纯
+函数，非 Agent；不变量 #3：状态变更是确定性扫描而非 AI 静默写库）。
+
+挂载方式（端点）：FastAPI `BackgroundTasks` 在 accept 端点登记 `run_overdue_scan`。
+BackgroundTask 在请求-response 发回、请求 session 关闭**之后**才跑——故本函数**自建新
+session**（不复用请求 session）并自己 `commit()`。
+
+**持久性局限（§7.4）**：BackgroundTasks 在 API 进程内跑，进程重启/崩溃会丢失未跑完的
+任务——原型可接受，这里把触发/完成/失败都记结构化日志便于查错；**不引入 `jobs` 表**
+（那是 M4/T4.1 的工作，本任务不越界）。
+
+可测性：扫描逻辑抽成纯 async 函数 `run_overdue_scan(session_factory, ...)`，端点用
+BackgroundTasks 调它；单测直接 `await` 它（注入 fake session 工厂）断言行被置 OVERDUE，
+**绝不真起不可控后台线程**。
+"""
+
+from __future__ import annotations
+
+import uuid
+from collections.abc import Callable
+from contextlib import AbstractAsyncContextManager
+from typing import Protocol
+
+import structlog
+from sqlalchemy.ext.asyncio import AsyncSession
+from ww_core.domain import ForeshadowLedgerView, SqlForeshadowLedgerRepo
+
+log = structlog.get_logger(__name__)
+
+# 新建独立 session 的工厂：调用得到一个 async 上下文管理器（`async with` → AsyncSession）。
+SessionFactory = Callable[[], AbstractAsyncContextManager[AsyncSession]]
+
+
+class OverdueScanRepo(Protocol):
+    """到期扫描对账本 repo 的最小依赖（仅 `scan_overdue`）。"""
+
+    async def scan_overdue(
+        self, project_id: uuid.UUID, *, current_chapter: int
+    ) -> list[ForeshadowLedgerView]: ...
+
+
+# repo 工厂：从新 session 造账本 repo。默认建 SQL 实现；测试注入 fake（避免真连 DB）。
+RepoFactory = Callable[[AsyncSession], OverdueScanRepo]
+
+
+def _default_repo_factory(session: AsyncSession) -> OverdueScanRepo:
+    return SqlForeshadowLedgerRepo(session)
+
+
+async def run_overdue_scan(
+    session_factory: SessionFactory,
+    *,
+    project_id: uuid.UUID,
+    chapter_no: int,
+    request_id: str | None = None,
+    repo_factory: RepoFactory = _default_repo_factory,
+) -> int:
+    """验收后伏笔到期扫描：新建 session → `scan_overdue` 置 OVERDUE → `commit()`。
+
+    返回被置 OVERDUE 的伏笔条数（供日志/测试断言）。任何异常被捕获并记错误日志后
+    吞掉——后台任务失败不应冒泡崩进程，也不影响已成功的验收事务（§7.4 局限可接受）。
+    `repo_factory` 是可注入缝：默认建 SQL 账本 repo，测试注 fake（直接 await、不联网）。
+    """
+    try:
+        async with session_factory() as session:
+            repo = repo_factory(session)
+            changed = await repo.scan_overdue(project_id, current_chapter=chapter_no)
+            if changed:
+                await session.commit()
+            log.info(
+                "foreshadow_overdue_scan",
+                project_id=str(project_id),
+                chapter_no=chapter_no,
+                request_id=request_id,
+                overdue_count=len(changed),
+                overdue_codes=[v.code for v in changed],
+            )
+            return len(changed)
+    except Exception as exc:  # noqa: BLE001 — 后台任务边界：记错误、不冒泡崩进程（§7.4）。
+        log.error(
+            "foreshadow_overdue_scan_failed",
+            project_id=str(project_id),
+            chapter_no=chapter_no,
+            request_id=request_id,
+            error=str(exc),
+        )
+        return 0
--- a/apps/api/ww_api/services/outline_context.py
+++ b/apps/api/ww_api/services/outline_context.py
@@ -0,0 +1,87 @@
+"""大纲生成的注入上下文组装（确定性序列化文本；ARCH §5.4 outliner reads / §6.2）。
+
+把 projects 设定 + 已登记伏笔 + 人物 + 世界观确定性序列化成纯文本喂给 outliner——
+**无时间戳/无 UUID**（缓存前缀稳定，不变量 #9），逐项排序保证同输入同输出（可单测）。
+outliner 据此排出分章节拍 + 伏笔回收窗口（关联本章与伏笔，§6.2）。
+
+注：reads=["projects","foreshadow","characters","world_entities"]（C6 outliner_spec），
+本组装恰好覆盖这四源，不读 digest/outline（排大纲是从设定生成、非续写既有章）。
+"""
+
+from __future__ import annotations
+
+from collections.abc import Sequence
+
+from ww_core.domain import ForeshadowLedgerView, ProjectView
+from ww_core.domain.repositories import CharacterView, WorldEntityView
+
+
+def _project_block(project: ProjectView) -> str:
+    lines = [f"标题：{project.title}"]
+    if project.genre:
+        lines.append(f"类型：{project.genre}")
+    if project.logline:
+        lines.append(f"一句话简介：{project.logline}")
+    if project.premise:
+        lines.append(f"前提：{project.premise}")
+    if project.theme:
+        lines.append(f"主题：{project.theme}")
+    if project.selling_points:
+        lines.append("卖点：" + "、".join(project.selling_points))
+    if project.structure:
+        lines.append(f"结构：{project.structure}")
+    return "【作品设定】\n" + "\n".join(lines)
+
+
+def _foreshadow_block(foreshadow: Sequence[ForeshadowLedgerView]) -> str:
+    if not foreshadow:
+        return "【已登记伏笔】\n（无）"
+    rows = sorted(foreshadow, key=lambda f: f.code)
+    lines = []
+    for f in rows:
+        window = ""
+        if f.expected_close_from is not None or f.expected_close_to is not None:
+            lo = f.expected_close_from if f.expected_close_from is not None else "?"
+            hi = f.expected_close_to if f.expected_close_to is not None else "?"
+            window = f"（回收窗口 {lo}-{hi}）"
+        plant = f"埋设第{f.planted_at}章 " if f.planted_at is not None else ""
+        lines.append(f"- [{f.code}] {f.title} {plant}{window}".rstrip())
+    return "【已登记伏笔】\n" + "\n".join(lines)
+
+
+def _characters_block(characters: Sequence[CharacterView]) -> str:
+    if not characters:
+        return "【人物】\n（无）"
+    rows = sorted(characters, key=lambda c: c.name)
+    lines = []
+    for c in rows:
+        role = f"（{c.role}）" if c.role else ""
+        motive = f" 动机：{c.motive}" if c.motive else ""
+        lines.append(f"- {c.name}{role}{motive}".rstrip())
+    return "【人物】\n" + "\n".join(lines)
+
+
+def _world_block(entities: Sequence[WorldEntityView]) -> str:
+    if not entities:
+        return "【世界观】\n（无）"
+    rows = sorted(entities, key=lambda e: (e.type, e.name))
+    lines = [f"- [{e.type}] {e.name}" for e in rows]
+    return "【世界观】\n" + "\n".join(lines)
+
+
+def build_outline_context(
+    *,
+    project: ProjectView,
+    foreshadow: Sequence[ForeshadowLedgerView],
+    characters: Sequence[CharacterView],
+    world_entities: Sequence[WorldEntityView],
+) -> str:
+    """组装 outliner 注入上下文（确定性文本，纯函数）。"""
+    return "\n\n".join(
+        [
+            _project_block(project),
+            _foreshadow_block(foreshadow),
+            _characters_block(characters),
+            _world_block(world_entities),
+        ]
+    )
--- a/apps/api/ww_api/services/project_deps.py
+++ b/apps/api/ww_api/services/project_deps.py
@@ -16,13 +16,15 @@ from openai import AsyncOpenAI
 from sqlalchemy import select
 from sqlalchemy.ext.asyncio import AsyncSession
 from ww_config import get_settings
+from ww_core.domain import ForeshadowLedgerRepo, SqlForeshadowLedgerRepo
 from ww_core.domain.chapter_repo import ChapterRepo, SqlChapterRepo
 from ww_core.domain.digest_repo import DigestAppendRepo, SqlDigestAppendRepo
+from ww_core.domain.outline_write_repo import OutlineWriteRepo, SqlOutlineWriteRepo
 from ww_core.domain.project_repo import ProjectRepo, SqlProjectRepo
 from ww_core.domain.repositories import MemoryRepos
 from ww_core.domain.review_repo import ReviewRepo, SqlReviewRepo
 from ww_core.memory.sql_repositories import sql_memory_repos
-from ww_db import get_session
+from ww_db import get_session, get_sessionmaker
 from ww_db.models import User
 from ww_llm_gateway import (
    Gateway,
@@ -42,6 +44,7 @@ from ww_api.services.credentials import (
    CredentialStore,
    SqlCredentialStore,
 )
+from ww_api.services.foreshadow_scan import SessionFactory
 from ww_api.services.provider_deps import _PROVIDER_BASE_URLS

 # 单用户 stub 的占位邮箱（多租户化时由真实主体替换）。
@@ -95,6 +98,30 @@ def get_digest_append_repo(
    return SqlDigestAppendRepo(session)


+def get_foreshadow_repo(
+    session: Annotated[AsyncSession, Depends(get_session)],
+) -> ForeshadowLedgerRepo:
+    """伏笔账本写侧 repo（登记/状态变更端点；只 flush，端点提交）。测试经 override 注 fake。"""
+    return SqlForeshadowLedgerRepo(session)
+
+
+def get_outline_write_repo(
+    session: Annotated[AsyncSession, Depends(get_session)],
+) -> OutlineWriteRepo:
+    """大纲写侧 repo（大纲生成端点逐章 upsert；只 flush，端点提交）。测试经 override 注 fake。"""
+    return SqlOutlineWriteRepo(session)
+
+
+def get_session_factory() -> SessionFactory:
+    """验收后到期扫描的**独立 session 工厂**缝。
+
+    BackgroundTask 在请求 session 关闭后才跑，必须自建 session（不复用 `get_session`）。
+    返回的工厂 `()` → `async with` 得一个新 `AsyncSession`。测试经 `app.dependency_overrides`
+    注入 fake 工厂（避免真起后台线程/真连 DB）。
+    """
+    return get_sessionmaker()
+
+
 async def build_gateway_for_tier(
    session: AsyncSession, store: CredentialStore, tier: Tier
 ) -> Gateway:
@@ -160,3 +187,11 @@ async def get_digest_gateway(
    """验收终稿 digest 提炼（light 档位）的可注入网关缝。测试经 override 注 mock。"""
    store = SqlCredentialStore(session)
    return await build_gateway_for_tier(session, store, "light")
+
+
+async def get_outline_gateway(
+    session: Annotated[AsyncSession, Depends(get_session)],
+) -> Gateway:
+    """大纲生成（analyst 档位）的可注入网关缝。测试经 override 注 mock（产 OutlineResult）。"""
+    store = SqlCredentialStore(session)
+    return await build_gateway_for_tier(session, store, "analyst")