Initial commit: Music Hub collaboration platform

Full-stack music production collaboration tool with:
- SvelteKit frontend with Design System (CSS vars, 8 shared components)
- Hono API with auth, projects, tracks, versions, comments
- PostgreSQL + Drizzle ORM (8 tables, roles, permissions)
- S3-compatible storage with presigned upload URLs
- wavesurfer.js audio player with waveform visualization
- A/B version comparison with synchronized playback
- Timestamped comments with threading and resolve workflow
- Magic Link authentication with Resend email integration
- Background audio processing (ffmpeg transcode + waveform peaks)
- Role-based access control (Owner, Engineers, Artist, Label, Management, Viewer)
- Toast notifications, skeleton loading, responsive layout
- Docker deployment setup (API + Web + Postgres)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.env.example

@@ -0,0 +1,8 @@
+DATABASE_URL=postgresql://musichub:musichub@localhost:5433/musichub
+S3_ENDPOINT=http://localhost:9000
+S3_ACCESS_KEY=minioadmin
+S3_SECRET_KEY=minioadmin
+S3_BUCKET=music-hub
+APP_URL=http://localhost:5173
+API_URL=http://localhost:3000
+MAGIC_LINK_SECRET=change-me-in-production