feat(web): F1/F2/F3 前端——拆书入库为规则 / 续写式链选择 / 模板库

- gen:api 纳入 /templates、chain continue_volume、teardown rules ingest 端点
- F1：GeneratorRunner 识别拆书为单对象入库（整 preview 作一条 teardown），
  ingestTable(BookTeardownResult)=rules，buildIngestRequest 组装 teardown 体，
  按 isSingleObjectIngest 隐藏勾选框、改文案「入库为规则」
- F2：ChainStarter 加链类型单选（draft_volume 从头写 / continue_volume 续写），
  chain_key 作 path 参传给 run（CHAIN_KINDS 对齐后端 SUPPORTED_CHAINS）
- F3：模板库页 app/templates + 全局 nav 入口 + TemplatesManager（列/建/删，乐观更新回滚）；
  GeneratorRunner 加 TemplateFiller「从模板填入」（body 填进 brief/text，纯前端）
- vitest 覆盖 templates/ingest teardown/templateFillTarget/CHAIN_KINDS 纯逻辑

apps/web/components/chain/ChainPage.tsx

@@ -5,7 +5,7 @@ import { useCallback, useEffect, useMemo, useState } from "react";
 import { AppShell } from "@/components/AppShell";
 import { useToast } from "@/components/Toast";
 import { api } from "@/lib/api/client";
-import { chainPhase, chainResultView } from "@/lib/chain/chain";
+import { chainPhase, chainResultView, type ChainKind } from "@/lib/chain/chain";
 import { friendlyError } from "@/lib/errors/messages";
 import { useJobPoll } from "@/lib/jobs/useJobPoll";
 import type { ProjectResponse } from "@/lib/api/types";
@@ -17,8 +17,6 @@ interface ChainPageProps {
   project: ProjectResponse;
 }
 
-const CHAIN_KEY = "draft_volume";
-
 // 多章工作流链页（Scope B B1）：发起链(POST run)→job 轮询进度→interrupt 命中则读该章冲突裁决→
 // POST resume 续跑。复用 useJobPoll（轮询）+ ConflictCard/decisions（裁决）+ friendlyError（文案）。
 // 链是后台任务，走 job 轮询而非 SSE。awaiting 时停轮询（后端把 job 置 awaiting_input，
@@ -43,14 +41,18 @@ export function ChainPage({ project }: ChainPageProps) {
   }, [phase, poll]);
 
   const onStart = useCallback(
-    async (startChapterNo: number, count: number): Promise<void> => {
+    async (
+      chainKey: ChainKind,
+      startChapterNo: number,
+      count: number,
+    ): Promise<void> => {
       setStarting(true);
       try {
         const { data, error } = await api.POST(
           "/projects/{project_id}/chains/{chain_key}/run",
           {
             params: {
-              path: { project_id: project.id, chain_key: CHAIN_KEY },
+              path: { project_id: project.id, chain_key: chainKey },
             },
             body: { start_chapter_no: startChapterNo, count },
           },
@@ -89,7 +91,10 @@ export function ChainPage({ project }: ChainPageProps) {
       activeNav="chains"
     >
       <div className="mx-auto flex w-full max-w-3xl flex-col gap-6 p-6">
-        <ChainStarter onStart={(s, c) => void onStart(s, c)} disabled={busy} />
+        <ChainStarter
+          onStart={(k, s, c) => void onStart(k, s, c)}
+          disabled={busy}
+        />
 
         {showProgress && result ? (
           <ChainProgress phase={phase} progress={poll.progress} result={result} />