Add configurable background music per level with song selector in the
level editor General tab. Update ship model, add base3 model, add
song2/song3 audio tracks, and clean up level config formatting.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
- Switch from svelte-spa-router to svelte-routing for clean URLs without hashes
- Fix relative asset paths to absolute paths (prevents 404s on nested routes)
- Fix physics engine disposal using scene.disablePhysicsEngine()
- Fix Ship observer cleanup to prevent stale callbacks after level disposal
- Add _gameplayStarted flag to prevent false game-end triggers during init
- Add hasAsteroidsToDestroy check to prevent false victory on restart
- Add RockFactory.reset() to properly reinitialize asteroid mesh between games
- Add null safety checks throughout RockFactory for static properties
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
