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/lib/chain/chain.test.ts

@@ -4,6 +4,7 @@ import { emptyDecisions, setNote, setVerdict } from "@/lib/review/decisions";
 import type { JobView } from "@/lib/jobs/job";
 import {
   buildResumeRequest,
+  CHAIN_KINDS,
   chainPhase,
   chainResultView,
 } from "./chain";
@@ -110,3 +111,19 @@ describe("buildResumeRequest", () => {
     expect(buildResumeRequest([])).toEqual({ decisions: [] });
   });
 });
+
+describe("CHAIN_KINDS", () => {
+  it("exposes both built-in chain kinds aligned with backend SUPPORTED_CHAINS", () => {
+    expect(CHAIN_KINDS.map((k) => k.key)).toEqual([
+      "draft_volume",
+      "continue_volume",
+    ]);
+  });
+
+  it("gives each kind a non-empty label and description", () => {
+    for (const kind of CHAIN_KINDS) {
+      expect(kind.label.length).toBeGreaterThan(0);
+      expect(kind.description.length).toBeGreaterThan(0);
+    }
+  });
+});