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/menu/data/dtos/menu_dto.dart

@@ -0,0 +1,102 @@
+import 'package:superport_v2/core/common/models/paginated_result.dart';
+
+import '../../domain/entities/menu.dart';
+
+class MenuDto {
+  MenuDto({
+    this.id,
+    required this.menuCode,
+    required this.menuName,
+    this.parent,
+    this.path,
+    this.displayOrder,
+    this.isActive = true,
+    this.isDeleted = false,
+    this.note,
+    this.createdAt,
+    this.updatedAt,
+  });
+
+  final int? id;
+  final String menuCode;
+  final String menuName;
+  final MenuSummaryDto? parent;
+  final String? path;
+  final int? displayOrder;
+  final bool isActive;
+  final bool isDeleted;
+  final String? note;
+  final DateTime? createdAt;
+  final DateTime? updatedAt;
+
+  factory MenuDto.fromJson(Map<String, dynamic> json) {
+    return MenuDto(
+      id: json['id'] as int?,
+      menuCode: json['menu_code'] as String,
+      menuName: json['menu_name'] as String,
+      parent: json['parent_menu'] is Map<String, dynamic>
+          ? MenuSummaryDto.fromJson(json['parent_menu'] as Map<String, dynamic>)
+          : json['parent'] is Map<String, dynamic>
+          ? MenuSummaryDto.fromJson(json['parent'] as Map<String, dynamic>)
+          : null,
+      path: json['path'] as String?,
+      displayOrder: json['display_order'] as int?,
+      isActive: (json['is_active'] as bool?) ?? true,
+      isDeleted: (json['is_deleted'] as bool?) ?? false,
+      note: json['note'] as String?,
+      createdAt: _parseDate(json['created_at']),
+      updatedAt: _parseDate(json['updated_at']),
+    );
+  }
+
+  MenuItem toEntity() => MenuItem(
+    id: id,
+    menuCode: menuCode,
+    menuName: menuName,
+    parent: parent?.toEntity(),
+    path: path,
+    displayOrder: displayOrder,
+    isActive: isActive,
+    isDeleted: isDeleted,
+    note: note,
+    createdAt: createdAt,
+    updatedAt: updatedAt,
+  );
+
+  static PaginatedResult<MenuItem> parsePaginated(Map<String, dynamic>? json) {
+    final items = (json?['items'] as List<dynamic>? ?? [])
+        .whereType<Map<String, dynamic>>()
+        .map(MenuDto.fromJson)
+        .map((dto) => dto.toEntity())
+        .toList();
+    return PaginatedResult<MenuItem>(
+      items: items,
+      page: json?['page'] as int? ?? 1,
+      pageSize: json?['page_size'] as int? ?? items.length,
+      total: json?['total'] as int? ?? items.length,
+    );
+  }
+}
+
+class MenuSummaryDto {
+  MenuSummaryDto({required this.id, required this.menuName});
+
+  final int id;
+  final String menuName;
+
+  factory MenuSummaryDto.fromJson(Map<String, dynamic> json) {
+    return MenuSummaryDto(
+      id: json['id'] as int,
+      menuName: json['menu_name'] as String,
+    );
+  }
+
+  MenuSummary toEntity() => MenuSummary(id: id, menuName: menuName);
+}
+
+DateTime? _parseDate(Object? value) {
+  if (value == null) return null;
+  if (value is DateTime) return value;
+  if (value is String) return DateTime.tryParse(value);
+  return null;
+}