- Unify directory structure across protocols:
* WebDAV: data/files/<username>/
* CalDAV: data/<username>/calendars/<name>/
* CardDAV: data/<username>/addressbooks/<name>/
- Add automatic migration capability that runs on server startup
- Maintain full backward compatibility with existing installations
- Improve Docker usage by automatically handling legacy data structure
- Updated storage provider implementations to use new nested structure
- Enhanced store functions for backward compatibility
- Modified CalDAV and CardDAV backends to use unified paths
- Added automatic migration logic in server initialization