feat: read-only MusicBrainz module + monitoring test cleanup

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

web/src/lib/musicbrainz.ts

@@ -0,0 +1,65 @@
+const MB_BASE = "https://musicbrainz.org/ws/2";
+const USER_AGENT = "Lyra/0.1 ( https://git.jger.nl/Jonathan/Lyra )";
+
+export type ArtistHit = { mbid: string; name: string; disambiguation: string };
+export type ReleaseGroupInfo = {
+  rgMbid: string;
+  title: string;
+  primaryType: string | null;
+  secondaryTypes: string[];
+  firstReleaseDate: string | null;
+};
+export type ReleaseGroupMatch = ReleaseGroupInfo & { artistMbid: string; artistName: string };
+
+async function mbGet(path: string): Promise<any> {
+  const res = await fetch(`${MB_BASE}${path}`, {
+    headers: { "User-Agent": USER_AGENT, Accept: "application/json" },
+  });
+  if (!res.ok) throw new Error(`MusicBrainz request failed: ${res.status}`);
+  return res.json();
+}
+
+function toReleaseGroup(g: any): ReleaseGroupInfo {
+  return {
+    rgMbid: g.id,
+    title: g.title ?? "",
+    primaryType: g["primary-type"] ?? null,
+    secondaryTypes: g["secondary-types"] ?? [],
+    firstReleaseDate: g["first-release-date"] || null,
+  };
+}
+
+export async function searchArtists(query: string): Promise<ArtistHit[]> {
+  const data = await mbGet(`/artist?query=${encodeURIComponent(query)}&fmt=json&limit=8`);
+  return (data.artists ?? []).map((a: any) => ({
+    mbid: a.id,
+    name: a.name ?? "",
+    disambiguation: a.disambiguation ?? "",
+  }));
+}
+
+export async function browseReleaseGroups(artistMbid: string): Promise<ReleaseGroupInfo[]> {
+  const out: ReleaseGroupInfo[] = [];
+  let offset = 0;
+  for (;;) {
+    const data = await mbGet(
+      `/release-group?artist=${encodeURIComponent(artistMbid)}&fmt=json&limit=100&offset=${offset}`,
+    );
+    const groups: any[] = data["release-groups"] ?? [];
+    for (const g of groups) out.push(toReleaseGroup(g));
+    offset += groups.length;
+    const total = data["release-group-count"] ?? offset;
+    if (groups.length === 0 || offset >= total) break;
+  }
+  return out;
+}
+
+export async function searchReleaseGroup(artist: string, album: string): Promise<ReleaseGroupMatch | null> {
+  const query = `releasegroup:"${album}" AND artist:"${artist}"`;
+  const data = await mbGet(`/release-group?query=${encodeURIComponent(query)}&fmt=json&limit=5`);
+  const groups: any[] = data["release-groups"] ?? [];
+  if (groups.length === 0) return null;
+  const g = groups[0];
+  const credit = g["artist-credit"]?.[0]?.artist ?? {};
+  return { ...toReleaseGroup(g), artistMbid: credit.id ?? "", artistName: credit.name ?? artist };
+}