feat(auth): Implement Google OAuth 2.0 integration with user creation and JWT generation

- Added Google OAuth controller and service to handle authentication via Google.
- Introduced DTOs for Google user and token responses.
- Updated AuthService and UsersService traits to support new Google OAuth functionality.
- Implemented logic to create a new user if they do not exist in the system after Google authentication.
- Enhanced existing user retrieval and JWT generation upon successful login.
- Added tests for Google OAuth flow, including login redirection and callback handling for both new and existing users.
- Updated environment configuration to include Google OAuth credentials.

imphnen-libs/src/jsonwebtoken/mod.rs

@@ -86,5 +86,9 @@ pub fn decode_refresh_token(
 		&Validation::default(),
 	)
 	.map_err(|_| StatusCode::INTERNAL_SERVER_ERROR);
-	result
+	result // Explicitly return result
+}
+
+pub fn generate_jwt(user_id: &str) -> Result<String, StatusCode> {
+    encode_access_token(user_id.to_string())
 }