fix: use iTunes lookup endpoint for explicit artist tracks

iTunes search endpoint always returns cleaned versions.
Added itunesLookupArtistSongs() using /lookup?explicit=Yes which returns
the actual explicit tracks. Used in artist profile (global search) and
artist detail page (library). Album track lookup also gets explicit=Yes.

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

src/api.js

@@ -43,7 +43,14 @@ export async function itunesSearch(query, entity='musicTrack', limit=25) {
 }
 
 export async function itunesLookupAlbum(collectionId) {
-  const r = await fetch(`${ITUNES}/lookup?id=${collectionId}&entity=song`);
+  const r = await fetch(`${ITUNES}/lookup?id=${collectionId}&entity=song&explicit=Yes`);
+  const d = await r.json();
+  return (d.results || []).filter(x => x.wrapperType === 'track');
+}
+
+// Returns actual explicit tracks for an artist via lookup (search endpoint only returns cleaned versions)
+export async function itunesLookupArtistSongs(artistId, limit=15) {
+  const r = await fetch(`${ITUNES}/lookup?id=${artistId}&entity=song&limit=${limit}&country=us&explicit=Yes`);
   const d = await r.json();
   return (d.results || []).filter(x => x.wrapperType === 'track');
 }