feat: 生命周期广播事件与链式钩子设施（ADR-006）

- contracts:补齐生命周期广播事件(订阅、下载、整理结束、刮削、字幕、作品关注 / 元数据 / 季集结构、站点可达性)
  的类型与 payload schema,LIFECYCLE_EVENTS 清单与 lifecycleKey 幂等键;HOOK_POINTS 链式钩子挂点;
  FEATURES 功能清单与 SLOT_POSITIONS 前端插槽位置
- outbox 中继支持一条事件路由给多个订阅方(其余订阅方用 <键>#<任务名>);生命周期事件允许多模块订阅,
  没有订阅方时也被中继认领并镜像到 SSE
- 服务端 HookRegistry:按注册顺序执行、rewrite / intercept 两类、单钩子超时与异常隔离、无注册零开销;
  ServerModule 增加 manifest 与 registerHooks,bootstrap 装配 ctx.hooks
- ADR-006 与 server README「如何写一个功能模块」

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01Cxwgnn2pbzQ7rXv3rq7fei

apps/server/vitest.config.ts

@@ -14,6 +14,8 @@ const UNIT = [
   "test/search/work-match.test.ts",
   "test/auth.test.ts",
   "test/health.test.ts",
+  "test/hooks/hook-registry.test.ts",
+  "test/hooks/resource-selection.test.ts",
   "test/sources-identity/identity-differential.test.ts",
   "test/sources-identity/enrich-sources.test.ts",
   "test/invoke-limits.test.ts",