v2.1.0:
• 15 languages with in-app language switcher
• Light, Dark, Black (OLED), and System themes
• Material You dynamic colors
• New M-equalizer app icon with themed icon support
• Server status indicator in top bar
• Audio-only mode and bitrate selector
• Thumbnail preview for YouTube URLs
• On-device result caching
• Foreground service for reliable background processing
• Rate limiting and input validation on API
• SQLite job persistence
• Docker support for server deployment
