feat(cache): 通用缓存按区统计与清空接口

GET /cache/regions 列出 kv_cache 各区的未过期条数、已过期条数、占用字节、最近写入;
POST /cache/regions/{region}/clear 清空一个区(admin)。contracts 加区名中文映射
cacheRegionLabel,web 加对应 hooks。

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

packages/contracts/src/cache.ts

@@ -75,3 +75,59 @@ export function tmdbImageUrl(path: string | null | undefined, size: TmdbImageSiz
   if (!/^[A-Za-z0-9_-]+\.(jpg|jpeg|png|webp)$/.test(p)) return null;
   return `/api/v1/img/tmdb/${size}/${p}`;
 }
+
+// ── 通用缓存(kv_cache)按 region 管理(设置 → 缓存) ──
+
+/** region 名:小写字母、数字、`.`、`_`、`-` */
+export const CacheRegionName = z.string().regex(/^[a-z0-9][a-z0-9._-]{0,63}$/, "缓存区名不合法");
+export const CacheRegionParam = z.object({ region: CacheRegionName });
+
+export const CacheRegionStat = z.object({
+  region: z.string(),
+  /** 未过期条目数 */
+  entries: NonNegInt,
+  /** 已过期、等清理任务删除的条目数 */
+  expired: NonNegInt,
+  /** 键与值占用字节(pg_column_size 之和,含已过期) */
+  bytes: NonNegInt,
+  /** 最近一次写入 */
+  lastWriteAt: Timestamp.nullable(),
+});
+export type CacheRegionStat = z.infer<typeof CacheRegionStat>;
+
+export const CacheRegionList = z.object({ items: z.array(CacheRegionStat) });
+export type CacheRegionList = z.infer<typeof CacheRegionList>;
+
+/** region → 界面名;精确匹配优先,其次按前缀(`bangumi.*`);都不中返回 null(界面原样显示 region) */
+const CACHE_REGION_LABELS: Record<string, string> = {
+  "tmdb.request": "TMDB 请求",
+  "tmdb.recognize": "TMDB 识别",
+  "douban.request": "豆瓣请求",
+  "douban.subject": "豆瓣条目",
+  "bangumi.request": "Bangumi 请求",
+  "bangumi.subject": "Bangumi 条目",
+  "meta.subject_miss": "豆瓣 / Bangumi 查无结果",
+  "discover.list": "发现列表",
+  "site.detail": "站点详情页",
+  "identity.detail_ids": "识别抓详情页计数",
+  enrich: "元数据补全",
+  "enrich.robots": "元数据补全 robots.txt",
+  websearch: "网页搜索",
+  "websearch.allow": "可读取的网页",
+  images: "图片",
+};
+const CACHE_REGION_PREFIX_LABELS: [string, string][] = [
+  ["tmdb.", "TMDB"],
+  ["douban.", "豆瓣"],
+  ["bangumi.", "Bangumi"],
+  ["discover.", "发现"],
+  ["site.", "站点"],
+  ["enrich.", "元数据补全"],
+  ["websearch.", "网页搜索"],
+];
+export function cacheRegionLabel(region: string): string | null {
+  const exact = CACHE_REGION_LABELS[region];
+  if (exact) return exact;
+  const hit = CACHE_REGION_PREFIX_LABELS.find(([p]) => region.startsWith(p));
+  return hit ? `${hit[1]}（${region.slice(hit[0].length)}）` : null;
+}