docs(changelog): track metadata-editor autofill bugs (album artist + multi-artist split)

iTunes/MusicBrainz autofill don't fill the Album-Artist field; multi-artist
lookup splitting is inconsistent across the two endpoints (neither handles
/, feat., ft.).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

CHANGELOG.md

@@ -234,3 +234,7 @@ Versioning: two-part `MAJOR.MINOR` — each release bumps the minor (features an
 - **Backend (metadata/sorting)** — iTunes `collectionArtistName` (album artist) is not captured,
   so `album_artist` can be wrong on compilations / various-artists releases, splitting albums and
   mis-sorting them in Navidrome.
+- **Metadata editor (autofill)** — The iTunes / MusicBrainz autofill buttons don't populate the
+  Album-Artist field (and iTunes autofill fills no artist at all). Multi-artist lookup is also
+  inconsistent: iTunes splits the artist on `; , &`, MusicBrainz on `, ; & •`, neither handles
+  `/`, `feat.`, `ft.`. Both should use one robust "first artist only" splitter for the search.