chore(about): update contributors, remove feature tagline, limit changelog to 3

- Add missing contributions: cucadmuh (PR #144, #167, #173, #174),
  kveld9 (PR #168), nisarg-78 (PR #115)
- Remove aboutFeatures tag line from all 8 locales (too dynamic to maintain)
- Changelog section now shows only the 3 most recent versions

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

src/locales/en.ts

@@ -542,7 +542,6 @@ export const enTranslation = {
     logout: 'Logout',
     aboutTitle: 'About Psysonic',
     aboutDesc: 'A modern desktop music player for Subsonic-compatible servers (Navidrome, Gonic, and others). Built on Tauri v2 with a native Rust audio engine — lightweight and fast, yet packed with features: waveform seekbar, synchronized lyrics, Last.fm integration, 10-band EQ, crossfade, gapless playback, Replay Gain, genre browsing, and a large library of themes.',
-    aboutFeatures: 'Multi-server · Last.fm scrobbling & love · Fullscreen Ambient Stage · Waveform seek · Synced lyrics · 10-band EQ · Crossfade & Gapless · Replay Gain · Genres · 8 languages',
     aboutLicense: 'License',
     aboutLicenseText: 'GNU GPL v3 — free to use, modify, and distribute under the same license.',
     aboutRepo: 'Source Code on GitHub',