docs: tidy CHANGELOG (drop duplicated [0.9] block) + refresh README

- CHANGELOG: remove the accidentally duplicated Changed/Fixed/Investigated
  block that sat orphaned before [0.8]; [0.9] now appears once.
- README: artist-pages bullet now mentions the same-name artist pin
  (Deezer link/id) and that a pinned artist's similar list comes from Deezer.

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

README.md

@@ -10,7 +10,7 @@ Built with Vite + vanilla ES modules (web) and Jetpack Compose + Media3/ExoPlaye
 - **Library** — Stream from Navidrome / Subsonic; browse artists, albums, playlists, genres, starred, and random; search; star + context menu on every row.
 - **Playback** — Queue with shuffle, repeat, and radio mode (endless similar songs); gapless-style preload; lock-screen / notification controls; Navidrome scrobbling.
 - **Lyrics** — Synced and plain lyrics via lrclib.net, auto-fetched and cached per session.
-- **Artist pages** — Hero card, Last.fm bio / similar / top songs, Ticketmaster events, and a Deezer cross-reference showing owned vs. missing tracks.
+- **Artist pages** — Hero card, bio / similar artists / top songs, Ticketmaster events, and a Deezer cross-reference showing owned vs. missing tracks. Same-name artists can be **pinned** (Deezer search or a pasted Deezer link/id) to fix the wrong-discography and wrong-photo problem; a pinned artist's similar list comes from Deezer.
 - **Playlists** — Create, rename, delete, add/remove tracks, and upload a cover (Web + Android).
 - **Importer & downloads** — Paste a Spotify / YouTube / YouTube Music / SoundCloud link to download via yt-dlp, with Deezer metadata enrichment and duplicate detection.
 - **Metadata editor** (web) — Edit tags + cover art; files are renamed/moved and Navidrome is rescanned on save.