- Introduced a new user model `yao/models/user.mod.yao` to support user management functionalities.
- Updated the OAuth service to utilize the new `DefaultUser` provider, enhancing user authentication and management capabilities.
- Refactored user retrieval methods to align with the new user model structure, ensuring compatibility and improved functionality.
- Added token management methods to the user provider interface, streamlining token handling processes.
- Enhanced test utilities to include the new user model for comprehensive testing coverage.
