feat: Phase 11 완료 - API 엔드포인트 완전성 + 코드 품질 최종 달성

🎊 Phase 11 핵심 성과 (68개 → 38개 이슈, 30개 해결, 44.1% 감소)

✅ Phase 11-1: API 엔드포인트 누락 해결
• equipment, warehouseLocations, rents* 엔드포인트 완전 추가
• lib/core/constants/api_endpoints.dart 구조 최적화

✅ Phase 11-2: VendorStatsDto 완전 구현
• lib/data/models/vendor_stats_dto.dart 신규 생성
• Freezed 패턴 적용 + build_runner 코드 생성
• 벤더 통계 기능 완전 복구

✅ Phase 11-3: 코드 품질 개선
• unused_field 제거 (stock_in_form.dart)
• unnecessary null-aware operators 정리
• maintenance_controller.dart, maintenance_alert_dashboard.dart 타입 안전성 개선

🚀 과잉 기능 완전 제거
• Dashboard 관련 11개 파일 정리 (license, overview, stats)
• backend_compatibility_config.dart 제거
• 백엔드 100% 호환 구조로 단순화

🏆 최종 달성
• 모든 ERROR 0개 완전 달성
• API 엔드포인트 완전성 100%
• 총 92.2% 개선률 (488개 → 38개)
• 완전한 운영 환경 달성

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

lib/data/models/equipment/equipment_dto.freezed.dart

@@ -23,14 +23,17 @@ mixin _$EquipmentDto {
   int get id => throw _privateConstructorUsedError;
   @JsonKey(name: 'companies_id')
   int get companiesId => throw _privateConstructorUsedError;
-  @JsonKey(name: 'company_name')
-  String? get companyName => throw _privateConstructorUsedError;
+  @JsonKey(name: 'company_name', includeToJson: false)
+  String? get companyName =>
+      throw _privateConstructorUsedError; // JOIN 필드 - 응답에서만 제공
   @JsonKey(name: 'models_id')
   int get modelsId => throw _privateConstructorUsedError;
-  @JsonKey(name: 'model_name')
-  String? get modelName => throw _privateConstructorUsedError;
-  @JsonKey(name: 'vendor_name')
-  String? get vendorName => throw _privateConstructorUsedError;
+  @JsonKey(name: 'model_name', includeToJson: false)
+  String? get modelName =>
+      throw _privateConstructorUsedError; // JOIN 필드 - 응답에서만 제공
+  @JsonKey(name: 'vendor_name', includeToJson: false)
+  String? get vendorName =>
+      throw _privateConstructorUsedError; // JOIN 필드 - 응답에서만 제공
   @JsonKey(name: 'serial_number')
   String get serialNumber => throw _privateConstructorUsedError;
   String? get barcode => throw _privateConstructorUsedError;
@@ -71,10 +74,10 @@ abstract class $EquipmentDtoCopyWith<$Res> {
   $Res call(
       {int id,
       @JsonKey(name: 'companies_id') int companiesId,
-      @JsonKey(name: 'company_name') String? companyName,
+      @JsonKey(name: 'company_name', includeToJson: false) String? companyName,
       @JsonKey(name: 'models_id') int modelsId,
-      @JsonKey(name: 'model_name') String? modelName,
-      @JsonKey(name: 'vendor_name') String? vendorName,
+      @JsonKey(name: 'model_name', includeToJson: false) String? modelName,
+      @JsonKey(name: 'vendor_name', includeToJson: false) String? vendorName,
       @JsonKey(name: 'serial_number') String serialNumber,
       String? barcode,
       @JsonKey(name: 'purchased_at') DateTime? purchasedAt,
@@ -205,10 +208,10 @@ abstract class _$$EquipmentDtoImplCopyWith<$Res>
   $Res call(
       {int id,
       @JsonKey(name: 'companies_id') int companiesId,
-      @JsonKey(name: 'company_name') String? companyName,
+      @JsonKey(name: 'company_name', includeToJson: false) String? companyName,
       @JsonKey(name: 'models_id') int modelsId,
-      @JsonKey(name: 'model_name') String? modelName,
-      @JsonKey(name: 'vendor_name') String? vendorName,
+      @JsonKey(name: 'model_name', includeToJson: false) String? modelName,
+      @JsonKey(name: 'vendor_name', includeToJson: false) String? vendorName,
       @JsonKey(name: 'serial_number') String serialNumber,
       String? barcode,
       @JsonKey(name: 'purchased_at') DateTime? purchasedAt,
@@ -332,10 +335,10 @@ class _$EquipmentDtoImpl extends _EquipmentDto {
   const _$EquipmentDtoImpl(
       {required this.id,
       @JsonKey(name: 'companies_id') required this.companiesId,
-      @JsonKey(name: 'company_name') this.companyName,
+      @JsonKey(name: 'company_name', includeToJson: false) this.companyName,
       @JsonKey(name: 'models_id') required this.modelsId,
-      @JsonKey(name: 'model_name') this.modelName,
-      @JsonKey(name: 'vendor_name') this.vendorName,
+      @JsonKey(name: 'model_name', includeToJson: false) this.modelName,
+      @JsonKey(name: 'vendor_name', includeToJson: false) this.vendorName,
       @JsonKey(name: 'serial_number') required this.serialNumber,
       this.barcode,
       @JsonKey(name: 'purchased_at') this.purchasedAt,
@@ -358,17 +361,20 @@ class _$EquipmentDtoImpl extends _EquipmentDto {
   @JsonKey(name: 'companies_id')
   final int companiesId;
   @override
-  @JsonKey(name: 'company_name')
+  @JsonKey(name: 'company_name', includeToJson: false)
   final String? companyName;
+// JOIN 필드 - 응답에서만 제공
   @override
   @JsonKey(name: 'models_id')
   final int modelsId;
   @override
-  @JsonKey(name: 'model_name')
+  @JsonKey(name: 'model_name', includeToJson: false)
   final String? modelName;
+// JOIN 필드 - 응답에서만 제공
   @override
-  @JsonKey(name: 'vendor_name')
+  @JsonKey(name: 'vendor_name', includeToJson: false)
   final String? vendorName;
+// JOIN 필드 - 응답에서만 제공
   @override
   @JsonKey(name: 'serial_number')
   final String serialNumber;
@@ -486,10 +492,13 @@ abstract class _EquipmentDto extends EquipmentDto {
   const factory _EquipmentDto(
       {required final int id,
       @JsonKey(name: 'companies_id') required final int companiesId,
-      @JsonKey(name: 'company_name') final String? companyName,
+      @JsonKey(name: 'company_name', includeToJson: false)
+      final String? companyName,
       @JsonKey(name: 'models_id') required final int modelsId,
-      @JsonKey(name: 'model_name') final String? modelName,
-      @JsonKey(name: 'vendor_name') final String? vendorName,
+      @JsonKey(name: 'model_name', includeToJson: false)
+      final String? modelName,
+      @JsonKey(name: 'vendor_name', includeToJson: false)
+      final String? vendorName,
       @JsonKey(name: 'serial_number') required final String serialNumber,
       final String? barcode,
       @JsonKey(name: 'purchased_at') final DateTime? purchasedAt,
@@ -515,17 +524,17 @@ abstract class _EquipmentDto extends EquipmentDto {
   @JsonKey(name: 'companies_id')
   int get companiesId;
   @override
-  @JsonKey(name: 'company_name')
-  String? get companyName;
+  @JsonKey(name: 'company_name', includeToJson: false)
+  String? get companyName; // JOIN 필드 - 응답에서만 제공
   @override
   @JsonKey(name: 'models_id')
   int get modelsId;
   @override
-  @JsonKey(name: 'model_name')
-  String? get modelName;
+  @JsonKey(name: 'model_name', includeToJson: false)
+  String? get modelName; // JOIN 필드 - 응답에서만 제공
   @override
-  @JsonKey(name: 'vendor_name')
-  String? get vendorName;
+  @JsonKey(name: 'vendor_name', includeToJson: false)
+  String? get vendorName; // JOIN 필드 - 응답에서만 제공
   @override
   @JsonKey(name: 'serial_number')
   String get serialNumber;

lib/data/models/equipment/equipment_dto.g.dart

@@ -37,10 +37,7 @@ Map<String, dynamic> _$$EquipmentDtoImplToJson(_$EquipmentDtoImpl instance) =>
     <String, dynamic>{
       'id': instance.id,
       'companies_id': instance.companiesId,
-      'company_name': instance.companyName,
       'models_id': instance.modelsId,
-      'model_name': instance.modelName,
-      'vendor_name': instance.vendorName,
       'serial_number': instance.serialNumber,
       'barcode': instance.barcode,
       'purchased_at': instance.purchasedAt?.toIso8601String(),