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

apps/web/lib/review/useReviewStream.ts

@@ -7,16 +7,24 @@ import {
   ReviewFrameBuffer,
   initialReviewState,
   reduceReview,
+  type ForeshadowSuggestion,
+  type PaceReport,
   type ReviewConflict,
   type ReviewStreamState,
 } from "./sse";
 
+export interface ReviewSeed {
+  conflicts: ReviewConflict[];
+  foreshadow: ForeshadowSuggestion[];
+  pace: PaceReport | null;
+}
+
 type Action =
   | { type: "start" }
   | { type: "events"; events: ReturnType<ReviewFrameBuffer["push"]> }
   | { type: "abort" }
   | { type: "fail"; code: string; message: string }
-  | { type: "seed"; conflicts: ReviewConflict[] };
+  | { type: "seed"; seed: ReviewSeed };
 
 function reducer(state: ReviewStreamState, action: Action): ReviewStreamState {
   switch (action.type) {
@@ -33,7 +41,12 @@ function reducer(state: ReviewStreamState, action: Action): ReviewStreamState {
         error: { code: action.code, message: action.message },
       };
     case "seed":
-      return { ...initialReviewState, conflicts: action.conflicts };
+      return {
+        ...initialReviewState,
+        conflicts: action.seed.conflicts,
+        foreshadow: action.seed.foreshadow,
+        pace: action.seed.pace,
+      };
     default:
       return state;
   }
@@ -45,8 +58,8 @@ export interface UseReviewStream {
   // 用当前编辑器草稿重新审稿。
   start: (projectId: string, chapterNo: number, draft: string) => Promise<void>;
   stop: () => void;
-  // 进页用历史留痕的冲突种入（无需重审即可裁决）。
-  seed: (conflicts: ReviewConflict[]) => void;
+  // 进页用历史留痕（冲突 + 伏笔建议 + 节奏）种入（无需重审即可裁决/查看）。
+  seed: (seed: ReviewSeed) => void;
 }
 
 // 消费 POST .../review 的 SSE 流：fetch+ReadableStream（EventSource 不支持 POST）。
@@ -62,8 +75,8 @@ export function useReviewStream(): UseReviewStream {
     dispatch({ type: "abort" });
   }, []);
 
-  const seed = useCallback((conflicts: ReviewConflict[]) => {
-    dispatch({ type: "seed", conflicts });
+  const seed = useCallback((seedData: ReviewSeed) => {
+    dispatch({ type: "seed", seed: seedData });
   }, []);
 
   const start = useCallback(