fix(auth): improve error handling in request-code handler

- Added logging for unexpected errors.
- Improved error handling using Logger.
- Replaced print statements with logging.
- Catches and logs stack traces.
- Uses HtHttpException for known exceptions.

Author: fulleni

routes/api/v1/auth/request-code.dart

@@ -3,6 +3,10 @@ import 'dart:io';
 import 'package:dart_frog/dart_frog.dart';
 import 'package:ht_api/src/services/auth_service.dart';
 import 'package:ht_shared/ht_shared.dart'; // For exceptions
+import 'package:logging/logging.dart';
+
+// Create a logger for this file.
+final _logger = Logger('request_code_handler');
 
 /// Handles POST requests to `/api/v1/auth/request-code`.
 ///
@@ -79,9 +83,9 @@ Future<Response> onRequest(RequestContext context) async {
   } on HtHttpException catch (_) {
     // Let the central errorHandler middleware handle known exceptions
     rethrow;
-  } catch (e) {
+  } catch (e, s) {
     // Catch unexpected errors from the service layer
-    print('Unexpected error in /request-code handler: $e');
+    _logger.severe('Unexpected error in /request-code handler', e, s);
     // Let the central errorHandler handle this as a 500
     throw const OperationFailedException(
       'An unexpected error occurred while requesting the sign-in code.',