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

apps/server/test/cache/region-admin.test.ts

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+import { PgCache } from "@umt/db";
+import { afterAll, beforeAll, describe, expect, it } from "vitest";
+import { createCacheModule } from "../../src/modules/cache/index.ts";
+import { bearer, createHarness, type Harness, pgAvailable } from "../auth-settings/harness.ts";
+import { DEV_KEY, json } from "../helpers.ts";
+
+// 设置 → 缓存:通用缓存(kv_cache)按区统计与单区清空(GET /cache/regions、POST /cache/regions/{region}/clear)
+
+const hasPg = await pgAvailable();
+
+describe.skipIf(!hasPg)("通用缓存按区管理(真实 PG)", () => {
+  let h: Harness;
+  let admin: ReturnType<typeof bearer>;
+
+  beforeAll(async () => {
+    h = await createHarness({ extraModules: [createCacheModule()] });
+    admin = bearer(h.app, DEV_KEY);
+  });
+  afterAll(async () => {
+    await h?.close();
+  });
+
+  it("按区列出未过期条数、已过期条数、占用字节、最近写入;清空一个区不影响其它区", async () => {
+    const cache = new PgCache(h.db);
+    await cache.set("douban.subject", "1", { title: "a" });
+    await cache.set("douban.subject", "2", { title: "b" });
+    await cache.set("site.detail", "x", { body: "y".repeat(200) });
+    // 写入后立刻过期的一条(ttl 1 秒,等它过期)
+    await cache.set("site.detail", "old", { v: 1 }, { ttl: 1 });
+    await new Promise((r) => setTimeout(r, 1100));
+
+    const res = await admin("GET", "/cache/regions");
+    expect(res.status).toBe(200);
+    const items = (await json(res)).data.items as {
+      region: string;
+      entries: number;
+      expired: number;
+      bytes: number;
+      lastWriteAt: string | null;
+    }[];
+    const douban = items.find((x) => x.region === "douban.subject")!;
+    const site = items.find((x) => x.region === "site.detail")!;
+    expect(douban).toMatchObject({ entries: 2, expired: 0 });
+    expect(douban.bytes).toBeGreaterThan(0);
+    expect(Date.parse(douban.lastWriteAt!)).toBeGreaterThan(Date.now() - 60_000);
+    expect(site).toMatchObject({ entries: 1, expired: 1 });
+    expect(site.bytes).toBeGreaterThan(200);
+
+    const cleared = await json(await admin("POST", "/cache/regions/site.detail/clear"));
+    expect(cleared.data.deleted).toBe(2);
+    const after = (await json(await admin("GET", "/cache/regions"))).data.items as { region: string }[];
+    expect(after.map((x) => x.region)).toContain("douban.subject");
+    expect(after.map((x) => x.region)).not.toContain("site.detail");
+    expect(await cache.count("douban.subject")).toBe(2);
+  });
+
+  it("区名不合法时拒绝(422),不执行删除", async () => {
+    const res = await admin("POST", "/cache/regions/BAD%20NAME/clear");
+    expect(res.status).toBe(422);
+  });
+});