userfront로 리펙토링 완료

userfront/lib/core/services/audit_service.dart

@@ -0,0 +1,45 @@
+import 'dart:convert';
+import 'package:http/http.dart' as http;
+import 'package:flutter_dotenv/flutter_dotenv.dart';
+
+class AuditService {
+  static String _envOrDefault(String key, String fallback) {
+    if (!dotenv.isInitialized) {
+      return fallback;
+    }
+    return dotenv.env[key] ?? fallback;
+  }
+
+  static String get _baseUrl => _envOrDefault('BACKEND_URL', 'https://sso.hmac.kr');
+
+  static Future<void> logEvent({
+    required String userId,
+    required String eventType,
+    required String status,
+    String? details,
+  }) async {
+    final url = Uri.parse('$_baseUrl/api/v1/audit');
+    
+    try {
+      final response = await http.post(
+        url,
+        headers: {'Content-Type': 'application/json'},
+        body: jsonEncode({
+          'user_id': userId,
+          'event_type': eventType,
+          'status': status,
+          'details': details,
+          'timestamp': DateTime.now().toIso8601String(),
+        }),
+      );
+
+      if (response.statusCode >= 200 && response.statusCode < 300) {
+        print("Audit log sent successfully");
+      } else {
+        print("Failed to send audit log: ${response.statusCode} ${response.body}");
+      }
+    } catch (e) {
+      print("Error sending audit log: $e");
+    }
+  }
+}