Add detailed documentation for multiple API endpoints and features:
- User playlists API with sharing and cloning endpoints
- Shared playlists API with access token generation
- Community playlists API for browsing/downloading
- Downloads API with SSE progress tracking
- Jobs API for scheduled task management
- Maintenance mode feature documentation
Update existing docs:
- Clarify Flashpoint vs User playlists distinction
- Add setup-status, most-played, and theme endpoints
- Expand settings cache and permission cache docs
- Reorganize API reference navigation structure
