feat(identity): web metadata enrichment for titles missing on TMDB (META-1)

- metadata.enrich (propose, low, replay safe): normalized-title cache (kv_cache
  region enrich, 7 days) -> daily budget -> web.search (title + 短剧 / 电视剧 平台,
  second query limited to whitelist via site:) -> web.fetch of up to 3 relevant
  whitelisted pages (registered site domains never read, redirects out of the
  whitelist dropped) -> upstream model extraction with rule fallback -> server-side
  evidence check (rule_confirmed / multi_evidence / needs_review). Suggestion only.
- POST /identity-pool/{id}/enrich (suggest) and /enrich/apply (console session):
  provisional entity or same-title merge, season/episode units, field-level
  metadata with source web/agent + evidence, aliases, release assignment.
  Poster proxy GET /img/enrich/{id} (og:image from whitelisted pages only).
- Auto-enrich once per pool entry when subscription/rule lookups find nothing on
  TMDB (identity.autoEnrich, off by default); identity.enrichDailyBudget,
  identity.enrichDomains settings; web.fetch now returns og:image.
- Pool sheet "元数据补全" section; entity detail shows evidence links.
- Migration 0049_enrichment (metadata_enrichment, metadata_field.evidence, source
  web). Requires image rebuild / api + worker restart to take effect.

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

docs/runbook/agent.md

@@ -6,7 +6,7 @@
 
 ## 能力
 
-启动时装配 38 个能力,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。描述符在 `packages/contracts/src/capability.ts`,每条描述都带一句"何时用 / 何时不用"。
+启动时装配 39 个能力,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。描述符在 `packages/contracts/src/capability.ts`,每条描述都带一句"何时用 / 何时不用"。
 
 | 分组 | 能力 |
 |---|---|
@@ -16,6 +16,7 @@
 | 原站浏览器 | `browser.snapshot`、`browser.navigate`、`browser.interact`、`browser.download`、`browser.screenshot`、`browser.click_at`、`browser.type_at`、`browser.scroll`、`browser.wait`、`browser.solve_challenge`(见 [browser.md](browser.md)) |
 | 会话 | `agent.plan`、`agent.propose_options`、`agent.spawn`、`agent.await` |
 | 网页搜索 | `web.search`、`web.fetch`(见 [websearch.md](websearch.md)) |
+| 元数据补全 | `metadata.enrich`(propose,只出建议;网页搜索开启才提供,见 [identity.md](identity.md#元数据补全meta-1)) |
 
 AG-3 补的只读摘要(类别 read,scope `read`,都在后台调查 / 巡检白名单里):