feat: Waveform seekbar, MilkDrop visualizer, EQ bars, in-app browser, and UX improvements (v1.3.0)

- PlayerBar redesigned: canvas waveform seekbar (500 bars, blue→mauve gradient + glow) replaces thin slider; new flex layout; queue toggle moved to content header (consistent with sidebar pattern)
- MilkDrop visualizer in Ambient Stage via Butterchurn; hidden audio analysis, preset shuffle, smooth blend transitions
- Tracklist: animated EQ bars for playing track, play icon when paused, align-items: center fix
- Artist pages: Last.fm + Wikipedia open in native Tauri WebviewWindow (in-app browser)
- Hero/Discover deduplication: single fetch of 20 random albums split between sections
- Update checker: runs every 10 minutes during runtime; version shown without v-prefix
- Settings version: now read from package.json instead of hardcoded
- Help page: new Random Mix section, updated Playback + Library sections, improved accordion styling
- Bump version to 1.3.0

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

package.json

@@ -1,6 +1,6 @@
 {
   "name": "psysonic",
-  "version": "1.2.0",
+  "version": "1.3.0",
   "private": true,
   "scripts": {
     "dev": "vite",
@@ -19,6 +19,8 @@
     "@tauri-apps/plugin-shell": "^2",
     "@tauri-apps/plugin-store": "^2",
     "axios": "^1.7.7",
+    "butterchurn": "^2.6.7",
+    "butterchurn-presets": "^2.4.7",
     "i18next": "^25.8.16",
     "lucide-react": "^0.462.0",
     "md5": "^2.3.0",