refactor(core): migrate to Bun and converge acquisition policies and Agent boundaries

apps/server/test/search/discover.test.ts

@@ -78,7 +78,7 @@ describe.skipIf(!up)("发现页接口", () => {
       settings: plainSettings(() => db),
       capabilities: createCapabilityRegistry({ logger }),
     } as ServerContext;
-    const metaFetch: typeof fetch = async (input, init) => {
+    const metaFetch: (input: RequestInfo | URL, init?: RequestInit) => Promise<Response> = async (input, init) => {
       const u = new URL(typeof input === "string" ? input : input instanceof URL ? input.href : input.url);
       meta.push(`${init?.method ?? "GET"} ${u.host}${u.pathname}${u.search}`);
       if (u.pathname.startsWith("/rexxar/api/v2/subject_collection/")) return doubanReply();