결재 템플릿 단계 적용 구현

- ApprovalTemplate 엔티티·DTO·원격 리포지토리 추가
- ApprovalController에 템플릿 로딩/적용 상태와 assignSteps 호출 연동
- ApprovalPage 단계 탭에 템플릿 선택 UI 및 적용 확인 다이얼로그 구현
- 템플릿 적용 단위 테스트와 IMPLEMENTATION_TASKS 현황 갱신

lib/features/masters/group/presentation/controllers/group_controller.dart

@@ -0,0 +1,152 @@
+import 'package:flutter/foundation.dart';
+import 'package:superport_v2/core/common/models/paginated_result.dart';
+
+import '../../domain/entities/group.dart';
+import '../../domain/repositories/group_repository.dart';
+
+enum GroupDefaultFilter { all, defaultOnly, nonDefault }
+
+enum GroupStatusFilter { all, activeOnly, inactiveOnly }
+
+/// 그룹 마스터 화면 상태 컨트롤러
+///
+/// - 목록 조회 및 필터, 페이징 상태를 담당한다.
+/// - 생성/수정/삭제/복구 요청을 래핑하여 UI와 통신한다.
+class GroupController extends ChangeNotifier {
+  GroupController({required GroupRepository repository})
+    : _repository = repository;
+
+  final GroupRepository _repository;
+
+  PaginatedResult<Group>? _result;
+  bool _isLoading = false;
+  bool _isSubmitting = false;
+  String _query = '';
+  GroupDefaultFilter _defaultFilter = GroupDefaultFilter.all;
+  GroupStatusFilter _statusFilter = GroupStatusFilter.all;
+  String? _errorMessage;
+
+  PaginatedResult<Group>? get result => _result;
+  bool get isLoading => _isLoading;
+  bool get isSubmitting => _isSubmitting;
+  String get query => _query;
+  GroupDefaultFilter get defaultFilter => _defaultFilter;
+  GroupStatusFilter get statusFilter => _statusFilter;
+  String? get errorMessage => _errorMessage;
+
+  Future<void> fetch({int page = 1}) async {
+    _isLoading = true;
+    _errorMessage = null;
+    notifyListeners();
+    try {
+      final isDefault = switch (_defaultFilter) {
+        GroupDefaultFilter.all => null,
+        GroupDefaultFilter.defaultOnly => true,
+        GroupDefaultFilter.nonDefault => false,
+      };
+      final isActive = switch (_statusFilter) {
+        GroupStatusFilter.all => null,
+        GroupStatusFilter.activeOnly => true,
+        GroupStatusFilter.inactiveOnly => false,
+      };
+      final response = await _repository.list(
+        page: page,
+        pageSize: _result?.pageSize ?? 20,
+        query: _query.isEmpty ? null : _query,
+        isDefault: isDefault,
+        isActive: isActive,
+      );
+      _result = response;
+    } catch (e) {
+      _errorMessage = e.toString();
+    } finally {
+      _isLoading = false;
+      notifyListeners();
+    }
+  }
+
+  void updateQuery(String value) {
+    _query = value;
+    notifyListeners();
+  }
+
+  void updateDefaultFilter(GroupDefaultFilter filter) {
+    _defaultFilter = filter;
+    notifyListeners();
+  }
+
+  void updateStatusFilter(GroupStatusFilter filter) {
+    _statusFilter = filter;
+    notifyListeners();
+  }
+
+  Future<Group?> create(GroupInput input) async {
+    _setSubmitting(true);
+    try {
+      final created = await _repository.create(input);
+      await fetch(page: 1);
+      return created;
+    } catch (e) {
+      _errorMessage = e.toString();
+      notifyListeners();
+      return null;
+    } finally {
+      _setSubmitting(false);
+    }
+  }
+
+  Future<Group?> update(int id, GroupInput input) async {
+    _setSubmitting(true);
+    try {
+      final updated = await _repository.update(id, input);
+      await fetch(page: _result?.page ?? 1);
+      return updated;
+    } catch (e) {
+      _errorMessage = e.toString();
+      notifyListeners();
+      return null;
+    } finally {
+      _setSubmitting(false);
+    }
+  }
+
+  Future<bool> delete(int id) async {
+    _setSubmitting(true);
+    try {
+      await _repository.delete(id);
+      await fetch(page: _result?.page ?? 1);
+      return true;
+    } catch (e) {
+      _errorMessage = e.toString();
+      notifyListeners();
+      return false;
+    } finally {
+      _setSubmitting(false);
+    }
+  }
+
+  Future<Group?> restore(int id) async {
+    _setSubmitting(true);
+    try {
+      final restored = await _repository.restore(id);
+      await fetch(page: _result?.page ?? 1);
+      return restored;
+    } catch (e) {
+      _errorMessage = e.toString();
+      notifyListeners();
+      return null;
+    } finally {
+      _setSubmitting(false);
+    }
+  }
+
+  void clearError() {
+    _errorMessage = null;
+    notifyListeners();
+  }
+
+  void _setSubmitting(bool value) {
+    _isSubmitting = value;
+    notifyListeners();
+  }
+}