fix: Random Mix improvements, queue UX fixes (v1.4.3)

- Random Mix: remove redundant Play All button in genre mix section
- Random Mix: Play All disabled with live counter during genre mix loading
- Random Mix: cap genre fetch at 50 genres to prevent over-fetching
- Random Mix: cache-bust getRandomSongs to always get fresh results
- Random Mix: clear songs on remix to fix display/play mismatch
- Queue: show song count and total duration in header
- Queue: context-active class keeps hover highlight on right-click
- Context Menu: add Favorite option for queue-item type

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

src-tauri/tauri.conf.json

@@ -1,7 +1,7 @@
 {
   "$schema": "https://schema.tauri.app/config/2",
   "productName": "Psysonic",
-  "version": "1.4.2",
+  "version": "1.4.3",
   "identifier": "dev.psysonic.app",
   "build": {
     "beforeDevCommand": "npm run dev",