승인 단계 삭제 복구 흐름 구현하고 API 정렬 문서 추가

lib/features/approvals/data/dtos/approval_dto.dart

@@ -194,6 +194,7 @@ class ApprovalStepDto {
     required this.assignedAt,
     this.decidedAt,
     this.note,
+    this.isDeleted = false,
   });
 
   final int? id;
@@ -203,6 +204,7 @@ class ApprovalStepDto {
   final DateTime assignedAt;
   final DateTime? decidedAt;
   final String? note;
+  final bool isDeleted;
 
   factory ApprovalStepDto.fromJson(Map<String, dynamic> json) {
     return ApprovalStepDto(
@@ -217,6 +219,10 @@ class ApprovalStepDto {
       assignedAt: _parseDate(json['assigned_at']) ?? DateTime.now(),
       decidedAt: _parseDate(json['decided_at']),
       note: json['note'] as String?,
+      isDeleted:
+          json['is_deleted'] as bool? ??
+          (json['deleted_at'] != null ||
+              (json['is_active'] is bool && !(json['is_active'] as bool))),
     );
   }
 
@@ -229,6 +235,7 @@ class ApprovalStepDto {
     assignedAt: assignedAt,
     decidedAt: decidedAt,
     note: note,
+    isDeleted: isDeleted,
   );
 }