feat(plugins): listenbrainz and lastfm

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

plugins/lastfm/src/options.ts

@@ -0,0 +1,8 @@
+/** Injectable sleep. Tests replace it with an immediate one via `setSleep`. */
+let sleepImpl: (ms: number) => Promise<void> = (ms) => Bun.sleep(ms);
+
+export function setSleep(fn: ((ms: number) => Promise<void>) | null): void {
+  sleepImpl = fn ?? ((ms) => Bun.sleep(ms));
+}
+
+export const sleep = (ms: number): Promise<void> => sleepImpl(ms);