Add sing-along lyric video generation (scrolling lyrics synced to music)

Description: Many users manually create lyric videos for their songs using external tools. It would be very helpful to have a built-in option in Songer to automatically generate a simple sing-along video. This would not be karaoke-style (no vocal removal or pitch guidance), but instead a clean video format that includes: The full song audio Timed, scrolling or line-by-line lyrics Optional simple background or cover art This would make it much easier for users to: Share songs on social media Create sing-along versions for friends and family Publish content without needing third-party editing tools This feature would significantly improve usability for creators who want to quickly turn songs into shareable video content.