web: migrate health notifications to js_interop; add browser hook

- Replace dart:js with package:js in health_check_service_web.dart\n- Implement showHealthCheckNotification in web/index.html\n- Pin js dependency to ^0.6.7 for flutter_secure_storage_web compatibility

auth: harden AuthInterceptor + tests

- Allow overrideAuthRepository injection for testing\n- Normalize imports to package: paths\n- Add unit test covering token attach, 401→refresh→retry, and failure path\n- Add integration test skeleton gated by env vars

ui/data: map User.companyName to list column

- Add companyName to domain User\n- Map UserDto.company?.name\n- Render companyName in user_list

cleanup: remove legacy equipment table + unused code; minor warnings

- Remove _buildFlexibleTable and unused helpers\n- Remove unused zipcode details and cache retry constant\n- Fix null-aware and non-null assertions\n- Address child-last warnings in administrator dialog

docs: update AGENTS.md session context

lib/data/repositories/auth_repository_impl.dart

@@ -181,6 +181,42 @@ class AuthRepositoryImpl implements AuthRepository {
     }
   }
 
+  @override
+  Future<Either<Failure, String?>> getStoredRefreshToken() async {
+    try {
+      final token = await _getRefreshToken();
+      return Right(token);
+    } catch (e) {
+      return Left(ServerFailure(
+        message: '리프레시 토큰 조회 중 오류가 발생했습니다: ${e.toString()}',
+      ));
+    }
+  }
+
+  @override
+  Future<Either<Failure, String?>> getStoredAccessToken() async {
+    try {
+      final token = await _getAccessToken();
+      return Right(token);
+    } catch (e) {
+      return Left(ServerFailure(
+        message: '액세스 토큰 조회 중 오류가 발생했습니다: ${e.toString()}',
+      ));
+    }
+  }
+
+  @override
+  Future<Either<Failure, void>> clearLocalSession() async {
+    try {
+      await _clearLocalData();
+      return const Right(null);
+    } catch (e) {
+      return Left(ServerFailure(
+        message: '로컬 세션 정리 중 오류가 발생했습니다: ${e.toString()}',
+      ));
+    }
+  }
+
   // Private 헬퍼 메서드들
   
   /// 액세스 토큰과 리프레시 토큰을 로컬에 저장