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/components/foreshadow/ForeshadowCard.tsx

@@ -0,0 +1,133 @@
+"use client";
+
+import { useState } from "react";
+
+import type { ForeshadowView } from "@/lib/api/types";
+import type { ForeshadowStatus } from "@/lib/foreshadow/board";
+
+interface ForeshadowCardProps {
+  item: ForeshadowView;
+  overdue: boolean;
+  busy: boolean;
+  onTransition: (
+    code: string,
+    toStatus: ForeshadowStatus | null,
+    progressNote: string,
+  ) => void;
+}
+
+const NEXT_STATUS: Record<string, ForeshadowStatus[]> = {
+  OPEN: ["PARTIAL", "CLOSED"],
+  PARTIAL: ["CLOSED"],
+  OVERDUE: ["PARTIAL", "CLOSED"],
+  CLOSED: [],
+};
+
+// 伏笔卡（UX §6.8）：code/title/回收窗口/importance/progress 时间线 + 状态变更/加进展。
+// OVERDUE 用琥珀强调（不单靠色：加 ⚠ 图标 + 文案，a11y §10）。
+export function ForeshadowCard({
+  item,
+  overdue,
+  busy,
+  onTransition,
+}: ForeshadowCardProps) {
+  const [note, setNote] = useState("");
+  const transitions = NEXT_STATUS[item.status] ?? [];
+  const windowText = recoveryWindow(item);
+
+  return (
+    <li
+      className={`rounded border bg-panel p-3 ${
+        overdue ? "border-overdue ring-1 ring-overdue/40" : "border-line"
+      }`}
+    >
+      <div className="flex items-baseline gap-2">
+        <span className="font-mono text-xs text-cinnabar">{item.code}</span>
+        {overdue ? (
+          <span className="text-xs text-overdue" aria-label="逾期">
+            ⚠ 逾期
+          </span>
+        ) : null}
+      </div>
+      <p className="mt-0.5 font-serif text-sm text-ink">{item.title}</p>
+
+      <dl className="mt-2 space-y-0.5 text-xs text-ink-soft">
+        {typeof item.planted_at === "number" ? (
+          <div>埋于 {item.planted_at} 章</div>
+        ) : null}
+        {windowText ? <div>窗口 {windowText}</div> : null}
+        {item.importance ? <div>{item.importance}</div> : null}
+      </dl>
+
+      {item.progress && item.progress.length > 0 ? (
+        <ul className="mt-2 border-l-2 border-line pl-2 text-xs text-ink-soft">
+          {item.progress.map((p, i) => (
+            <li key={i}>· {progressLabel(p)}</li>
+          ))}
+        </ul>
+      ) : null}
+
+      {transitions.length > 0 || item.status !== "CLOSED" ? (
+        <div className="mt-3 space-y-2">
+          {transitions.length > 0 ? (
+            <div className="flex flex-wrap gap-1.5">
+              {transitions.map((to) => (
+                <button
+                  key={to}
+                  type="button"
+                  disabled={busy}
+                  onClick={() => onTransition(item.code, to, "")}
+                  className="rounded border border-line px-2 py-0.5 text-xs text-ink hover:border-cinnabar hover:text-cinnabar disabled:opacity-40"
+                >
+                  → {to === "CLOSED" ? "回收" : to}
+                </button>
+              ))}
+            </div>
+          ) : null}
+          {item.status !== "CLOSED" ? (
+            <div className="flex gap-1.5">
+              <label htmlFor={`prog-${item.code}`} className="sr-only">
+                {item.code} 进展
+              </label>
+              <input
+                id={`prog-${item.code}`}
+                type="text"
+                value={note}
+                onChange={(e) => setNote(e.target.value)}
+                placeholder="加进展（如：23章发光）"
+                className="min-w-0 flex-1 rounded border border-line bg-bg px-2 py-0.5 text-xs text-ink focus:border-cinnabar focus:outline-none"
+              />
+              <button
+                type="button"
+                disabled={busy || note.trim().length === 0}
+                onClick={() => {
+                  onTransition(item.code, null, note.trim());
+                  setNote("");
+                }}
+                className="rounded border border-line px-2 py-0.5 text-xs text-ink hover:border-cinnabar disabled:opacity-40"
+              >
+                记
+              </button>
+            </div>
+          ) : null}
+        </div>
+      ) : null}
+    </li>
+  );
+}
+
+function recoveryWindow(item: ForeshadowView): string | null {
+  const from = item.expected_close_from;
+  const to = item.expected_close_to;
+  if (typeof from === "number" && typeof to === "number") return `${from}-${to}`;
+  if (typeof to === "number") return `≤${to}`;
+  if (typeof from === "number") return `≥${from}`;
+  return null;
+}
+
+function progressLabel(entry: Record<string, unknown>): string {
+  const chapter = entry["chapter"];
+  const note = entry["note"];
+  const noteStr = typeof note === "string" ? note : JSON.stringify(entry);
+  return typeof chapter === "number" ? `${chapter}章：${noteStr}` : noteStr;
+}