The web Apple-Music search proxies through /api/itunes (browsers can't call
itunes.apple.com — no CORS). The proxy forwarded every request uncached, so heavy
download activity (each download does several album/track lookups) plus client
searches blew past Apple's ~20 req/min/IP limit and the search started returning
nothing. Add a 30-min in-memory cache keyed by the target URL; only genuine 200
responses (with the resultCount signature) are cached, never throttle/error pages.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>