feat(agent): web.search / web.fetch via Brave Search (WEB-1)

- adapters/websearch: Brave client (X-Subscription-Token, error classes),
  result normalization with redaction/truncation, SSRF guard, HTML→text fetch
  (10s, 512KB, text/html|text/plain only)
- modules/websearch: 10-min PG cache (region websearch), cross-process
  per-minute limit, web.fetch allowlist = URLs from the caller's latest
  web.search; POST /websearch/test
- settings.agent.webSearch (key write-only → secret_ref); settings card
  under Agent; web.* offered to the model only when enabled, plus a system
  prompt rule; outputs marked untrusted
- capability count 27 → 29; e2e E13; runbook docs/runbook/websearch.md

Co-Authored-By: Claude Opus 5.5 <[email protected]>

docs/runbook/agent.md

@@ -6,7 +6,7 @@
 
 ## 能力
 
-启动时装配 15 个能力(`catalog.lookup`、`release.search`、`release.inspect`、`identity.resolve`、`download.plan`、`download.submit`、`download.recheck`、`organize.plan`、`organize.execute`、`task.inspect`、`task.retry`、`task.cancel`、`policy.preview`、`policy.apply`、`inventory.query`)。注册数不等于 `CAPABILITY_IDS.length` 时进程启动失败。Web(`POST /capabilities/{id}/invoke`)、Pi 工具和后台任务都走 `ctx.capabilities.invoke` 这一条路径。
+启动时装配 15 个能力(`catalog.lookup`、`release.search`、`release.inspect`、`identity.resolve`、`download.plan`、`download.submit`、`download.recheck`、`organize.plan`、`organize.execute`、`task.inspect`、`task.retry`、`task.cancel`、`policy.preview`、`policy.apply`、`inventory.query`)。注册数不等于 `CAPABILITY_IDS.length` 时进程启动失败。网页搜索 `web.search` / `web.fetch` 见 [websearch.md](websearch.md)。Web(`POST /capabilities/{id}/invoke`)、Pi 工具和后台任务都走 `ctx.capabilities.invoke` 这一条路径。
 
 - **授权**(`agent/authorize.ts`):propose / approve / execute 类必须满足以下之一:
   - 单次审批 `approval`:状态为 approved,绑定计划类型 + 计划 ID + payload hash + revision,且未过期。执行成功后审批标记为 consumed。
@@ -271,6 +271,7 @@ curl -X POST localhost:4380/api/v1/agent/runs -H "Authorization: Bearer umt-dev-
 | `e6-auto-recover` | qB missingFiles → download_failed → 授权内恢复(task.inspect → download.recheck → 系统核实关闭事项);无授权时降级只调查;换源被拒;去重;同根因尝试上限;预算超限保持待处理 |
 | `e11-subagents` | 父会话派生两个只读子会话并等待后汇总;maxConcurrent=1 时串行;子会话超预算不影响父;合计用量;子会话事件进父事件流;越权 / 提权 / 深度 / 关闭被拒;父中止后子会话 cancelled |
 | `e12-interaction` | 步骤清单先于业务调用、revision 递增;先看方案时执行被拒;方案选择挂起(waiting + await_wake)、选定 / 都不要 / 超时自动选推荐项后续跑;旧 `mode=plan_only` 按先看方案处理;管理员会话发起的会话内审批:批准后重放执行、审批 consumed,拒绝后以理由失败并写待处理事项 |
+| `e13-websearch` | 网页搜索:关闭时不提供 web.*;Key 只写存 secret;`POST /websearch/test`;「查一下某站点最近的公告」→ web.search → web.fetch → 汇报,搜索前 / 白名单外 / 内网地址的 web.fetch 被拒且不发请求;相同搜索走缓存 |
 
 ## 已知限制