fix(auth): send email with template ID

- Added sender email to email sending
- Used environment config for template ID
- Improved email sending robustness

Author: fulleni

lib/src/services/auth_service.dart

@@ -1,5 +1,6 @@
 import 'dart:async';
 
+import 'package:ht_api/src/config/environment_config.dart';
 import 'package:ht_api/src/rbac/permission_service.dart';
 import 'package:ht_api/src/rbac/permissions.dart';
 import 'package:ht_api/src/services/auth_token_service.dart';
@@ -102,7 +103,12 @@ class AuthService {
           .generateAndStoreSignInCode(email);
 
       // Send the code via email
-      await _emailRepository.sendOtpEmail(recipientEmail: email, otpCode: code);
+      await _emailRepository.sendOtpEmail(
+        senderEmail: EnvironmentConfig.defaultSenderEmail,
+        recipientEmail: email,
+        templateId: EnvironmentConfig.otpTemplateId,
+        otpCode: code,
+      );
       _log.info('Initiated email sign-in for $email, code sent.');
     } on HtHttpException {
       // Propagate known exceptions from dependencies or from this method's logic.