♻️ Refactor OpenID: Phase 3: Async Flow Modernization

- Added async GetAuthorizationUrlAsync() methods to all OIDC providers
- Updated base OidcService with abstract async contract and backward-compatible sync wrapper
- Modified OidcController to use async authorization URL generation
- Removed sync blocks using .GetAwaiter().GetResult() in Google provider
- Maintained backward compatibility with existing sync method calls
- Eliminated thread blocking and improved async flow throughout auth pipeline
- Enhanced scalability by allowing non-blocking async authorization URL generation

DysonNetwork.Pass/Auth/OpenId/OidcController.cs

@@ -43,7 +43,7 @@ public class OidcController(
                 await cache.SetAsync($"{StateCachePrefix}{state}", oidcState, StateExpiration);
 
                 // The state parameter sent to the provider is the GUID key for the cache.
-                var authUrl = oidcService.GetAuthorizationUrl(state, nonce);
+                var authUrl = await oidcService.GetAuthorizationUrlAsync(state, nonce);
                 return Redirect(authUrl);
             }
             else // Otherwise, proceed with the login / registration flow
@@ -54,7 +54,7 @@ public class OidcController(
                 // Create login state with return URL and device ID
                 var oidcState = OidcState.ForLogin(returnUrl ?? "/", deviceId);
                 await cache.SetAsync($"{StateCachePrefix}{state}", oidcState, StateExpiration);
-                var authUrl = oidcService.GetAuthorizationUrl(state, nonce);
+                var authUrl = await oidcService.GetAuthorizationUrlAsync(state, nonce);
                 return Redirect(authUrl);
             }
         }
@@ -194,4 +194,4 @@ public class OidcController(
 
         return newAccount;
     }
-}
+}