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]>

packages/contracts/test/db-sync.test.ts

@@ -95,6 +95,8 @@ const ROWS: Record<string, { row: Obj; dbOnly?: string[]; apiOnly?: string[] }>
   IdentityCandidate: { row: C.IdentityCandidate },
   IdentityRedirect: { row: C.IdentityRedirect },
   MetadataField: { row: C.MetadataField },
+  // META-1 元数据补全记录(0049)
+  MetadataEnrichment: { row: C.MetadataEnrichment },
   ResolutionAttempt: { row: C.ResolutionAttempt },
   SiteSnapshot: { row: C.SiteSnapshot },
   // W4-C 浏览器实体(0023)
@@ -265,6 +267,8 @@ const ENUMS: Record<string, z.ZodEnum> = {
   IdentityCandidateReason: C.IdentityCandidateReason,
   IdentityRedirectActorType: C.ActorType,
   MetadataFieldSource: C.MetadataSource,
+  MetadataEnrichmentStatus: C.EnrichmentStatus,
+  MetadataEnrichmentTrigger: C.EnrichmentTrigger,
   ResolutionAttemptOutcome: C.ResolutionOutcome,
   ResolutionAttemptActorType: C.ActorType,
   SiteSnapshotKind: C.SiteSnapshotKind,