feat: flow 第 1 部分（骨架、研究开始、第零轮）与第零轮检验

按任务书 12 实现 src/flow：从账本现算下一步的纯函数、主循环、恢复入口、派模型任务和跑正式运行两个共用动作、冻结配置、基线、第零轮三个研究者阶段和入口分配，走到第 1 轮时停下。materials 导出 finalEntries、加 researcherId 和 StudyRecord。

审阅采纳两条：研究编号本机已用过时冻结前报错；docker run 没启动时写完结果就停下，不在本进程里无限起新编号。

eval/ 新增第零轮检验：起研究命令行、回放假模型、检验用 Jev 客户端、六问质量评估、16-real-1 回放、杀进程与两份同时跑。tsc 与 depcruise 也检查 eval/，新增 eval 只经 index.ts 用正式代码的规则。

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

eval/lib/ledger.ts

@@ -0,0 +1,89 @@
+import { existsSync } from "node:fs";
+import { join } from "node:path";
+import { Ledger, type LedgerRecord } from "../../src/ledger/index.ts";
+import { entryId, type DecisionShapes } from "../../src/materials/index.ts";
+
+// 读账本的小工具：只经 src/ledger/index.ts 打开、只读记录，不写。
+// 入口编号用 materials 的 entryId，和正式代码同一条编号规则。
+
+/** 研究目录里账本的全部记录。账本还没有时报错：Ledger.open 会新建一个空账本，检验不能替 flow 建。 */
+export function readLedger(studyDir: string): LedgerRecord[] {
+  const path = join(studyDir, "ledger.sqlite");
+  if (!existsSync(path)) throw new Error(`${path} 还不存在`);
+  const ledger = Ledger.open(path);
+  try {
+    return ledger.records();
+  } finally {
+    ledger.close();
+  }
+}
+
+export type Of<K extends LedgerRecord["kind"]> = Extract<LedgerRecord, { kind: K }>;
+export function ofKind<K extends LedgerRecord["kind"]>(records: LedgerRecord[], kind: K): Array<Of<K>> {
+  return records.filter((r): r is Of<K> => r.kind === kind);
+}
+
+export interface StageInfo {
+  stageId: string;
+  stage: string;
+  round: number;
+  roster: string[];
+  closed: boolean;
+}
+
+export function stages(records: LedgerRecord[]): StageInfo[] {
+  const closed = new Set(ofKind(records, "stageClose").map((r) => r.content.stageId));
+  return ofKind(records, "stageOpen").map(({ content: c }) => ({ ...c, closed: closed.has(c.stageId) }));
+}
+
+/** 每份提交（阶段、作者、种类、对象、编号）的最新一版，按这一版的序号排。 */
+export function finalSubmissions(records: LedgerRecord[]): Array<Of<"submission">> {
+  const latest = new Map<string, Of<"submission">>();
+  for (const r of ofKind(records, "submission")) {
+    const c = r.content;
+    const slot = JSON.stringify([c.stageId, c.author, c.kind, c.target, c.item]);
+    const seen = latest.get(slot);
+    if (seen === undefined || seen.content.version < c.version) latest.set(slot, r);
+  }
+  return [...latest.values()].sort((a, b) => a.seq - b.seq);
+}
+
+export interface Entry {
+  id: string;
+  author: string;
+  name: string;
+  body: string;
+}
+
+/**
+ * 只看给定阶段里的提交，各人最后一版入口清单里的入口（方法.md 4.2：讨论时整份替换的新清单接着往后编号）。
+ * 给第零轮全部阶段就是分配时的"入口全体"；只给写入口阶段就是闭门写完时的入口全体。
+ */
+export function entriesIn(records: LedgerRecord[], stageIds: ReadonlySet<string>): Entry[] {
+  const lists = new Map<string, Entry[]>();
+  const used = new Map<string, number>();
+  for (const s of finalSubmissions(records)) {
+    const c = s.content;
+    if (!stageIds.has(c.stageId) || (c.kind !== "entry" && c.kind !== "discussion")) continue;
+    const entries = (c.content as { entries?: Array<{ name: string; body: string }> }).entries;
+    if (entries === undefined) continue;
+    const n = used.get(c.author) ?? 0;
+    lists.set(c.author, entries.map((e, i) => ({ id: entryId(c.author, n + i + 1), author: c.author, ...e })));
+    used.set(c.author, n + entries.length);
+  }
+  return [...lists.values()].flat();
+}
+
+export type Assignment = DecisionShapes["entries"]["output"][number];
+
+/** 第 0 轮的入口分配决定：输入（全部志愿和入口）和输出（分配结果）；没有就是 undefined。 */
+export function entryDecision(records: LedgerRecord[]): { input: { entries: Array<{ id: string; author: string }> }; output: Assignment[] } | undefined {
+  const d = ofKind(records, "decision").find((r) => r.content.decision === "entries" && r.content.round === 0);
+  return d === undefined ? undefined : (d.content as unknown as { input: { entries: Array<{ id: string; author: string }> }; output: Assignment[] });
+}
+
+/** 两份分配是否相同：每人分到的入口和第几志愿都一样，不看先后和对象里键的顺序。 */
+export function sameAssignment(a: Assignment[], b: Assignment[]): boolean {
+  const key = (xs: Assignment[]) => xs.map((x) => `${x.researcher} ${x.entry} ${x.rank}`).sort().join("\n");
+  return key(a) === key(b);
+}