- Deleted the OAuth interface and related types that were previously defined in the `interfaces.go` and `types.go` files, streamlining the codebase.
- Updated the `oauth.go` file to integrate user and client providers directly, enhancing the service's functionality and reducing complexity.
- Refactored the user information retrieval method to utilize the new user provider structure, ensuring compatibility with the updated architecture.
- Introduced the OAuth service structure, including configuration management and user provider integration.
- Implemented default settings and validation for various configuration parameters, ensuring robust service initialization.
- Added methods for retrieving service configuration and user information based on access tokens.
- Defined error handling for configuration issues, enhancing reliability of the OAuth service.
