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/enviroment/mod.rs

@@ -27,6 +27,10 @@ pub struct Env {
     pub minio_bucket_name: String,
     pub minio_access_key: String,
     pub minio_secret_key: String,
+    // Google OAuth 2.1
+    pub google_client_id: String,
+    pub google_client_secret: String,
+    pub google_redirect_url: String,
 }
 
 /// Helper to get env var with warning if not set.
@@ -74,5 +78,9 @@ pub static ENV: Lazy<Env> = Lazy::new(|| {
         minio_access_key: get_env_with_warning("MINIO_ACCESS_KEY", "minio_access"),
         minio_secret_key: get_env_with_warning("MINIO_SECRET_KEY", "minio_secret"),
         surrealdb_url_ws: String::new(),
+        // Google OAuth 2.1
+        google_client_id: get_env_with_warning("GOOGLE_CLIENT_ID", "default_google_client_id"),
+        google_client_secret: get_env_with_warning("GOOGLE_CLIENT_SECRET", "default_google_client_secret"),
+        google_redirect_url: get_env_with_warning("GOOGLE_REDIRECT_URL", "http://localhost:8000/api/v1/auth/google/callback"),
     }
 });

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())
 }