v2.4

v2.4 introduces Spotify search and playlist building, allowing users to create card sets by searching for songs directly instead of uploading a CSV.

Added

• Spotify search endpoint with track search API
• SpotifySearch component with real-time search results
• Playlist builder with add/remove functionality
• Genre assignment for playlist tracks
• Landing page with dual-path choice (CSV upload or playlist builder)
• Direct flow from playlist builder to card preview

Fixed

• Vite dev server now binds to all interfaces for proper port forwarding