feat(qq): include albums in search results

Add mapQqAlbums pure helper (exported, TDD-covered) and wire a parallel
req_album sub-request (search_type: 8) into search(), populating the
albums field of SearchResult.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/music/qq.test.ts

@@ -0,0 +1,43 @@
+import { describe, it, expect } from "vitest";
+import { mapQqAlbums } from "./qq.js";
+
+describe("QQ adapter", () => {
+  it("mapQqAlbums maps albumMID-style raw entries", () => {
+    const raw = [
+      {
+        albumMID: "abc",
+        albumName: "Aero",
+        singerName: "Singer A",
+      },
+      {
+        albumMID: "xyz",
+        albumName: "Beta",
+        singer: [{ name: "Singer B" }, { name: "Singer C" }],
+      },
+    ];
+    const out = mapQqAlbums(raw);
+    expect(out).toHaveLength(2);
+    expect(out[0]).toMatchObject({
+      id: "abc",
+      name: "Aero",
+      artist: "Singer A",
+      platform: "qq",
+    });
+    expect(out[0].coverUrl).toContain("T002R300x300M000abc.jpg");
+    expect(out[1].artist).toBe("Singer B / Singer C");
+    expect(out[1].coverUrl).toContain("xyz");
+  });
+
+  it("mapQqAlbums returns [] for empty/null input", () => {
+    expect(mapQqAlbums([])).toEqual([]);
+    expect(mapQqAlbums(null as any)).toEqual([]);
+    expect(mapQqAlbums(undefined as any)).toEqual([]);
+  });
+
+  it("mapQqAlbums falls back to albumPic when no albumMID", () => {
+    const raw = [{ albumName: "C", albumPic: "https://x/p.jpg", singerName: "S" }];
+    const out = mapQqAlbums(raw);
+    expect(out[0].coverUrl).toBe("https://x/p.jpg");
+    expect(out[0].id).toBe("");
+  });
+});