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/src/content.ts

@@ -1,6 +1,6 @@
 import { z } from "zod";
 import { ActorType, DateOnly, EntityBase, Id, JsonObject, SERVER_MANAGED, Timestamp } from "./common.ts";
-import { ExternalIdentity } from "./identity.ts";
+import { ExternalIdentity, FieldEvidence } from "./identity.ts";
 
 // 内容域:本地作品、内容单元、别名(REQ §3.1、§5.1、§5.4、§7.5)
 // 本地 UUID 是主身份;季/集编号、外部 ID 都可修订,不是唯一身份。
@@ -149,7 +149,8 @@ export type TitleAliasUpdate = z.infer<typeof TitleAliasUpdate>;
 
 // ── W2-B:字段级元数据(REQ §7.3)与作品详情 ──
 
-export const MetadataSource = z.enum(["tmdb", "user", "agent", "nfo", "site", "import"]);
+/** web = 值出自网页原文(META-1 补全);agent = Agent 归纳 / 翻译的生成内容。两者都不冒充 TMDB */
+export const MetadataSource = z.enum(["tmdb", "user", "agent", "nfo", "site", "import", "web"]);
 export type MetadataSource = z.infer<typeof MetadataSource>;
 
 /** 某来源给出的一个候选字段值(刷新只写这里,不直接改最终展示值) */
@@ -162,6 +163,8 @@ export const MetadataField = EntityBase.extend({
   source: MetadataSource,
   sourceRevision: z.string().nullable(),
   fetchedAt: Timestamp,
+  /** 字段证据(META-1 补全写入:来源网页、证据等级、补全记录);TMDB 等 API 来源为 null */
+  evidence: FieldEvidence.nullable().optional(),
 });
 export type MetadataField = z.infer<typeof MetadataField>;
 
@@ -190,6 +193,11 @@ export const EntityMetadataField = z.enum([
   "originCountry",
   "posterPath",
   "backdropPath",
+  // META-1 补全(TMDB 没有的作品):播出平台、集数、类型、网页海报地址(经图片代理显示)
+  "platform",
+  "episodeCount",
+  "genres",
+  "posterUrl",
 ]);
 export type EntityMetadataField = z.infer<typeof EntityMetadataField>;