fix: API 응답 파싱 오류 수정 및 에러 처리 개선

주요 변경사항:
- 창고 관리 API 응답 구조와 DTO 불일치 수정
  - WarehouseLocationDto에 code, manager_phone 필드 추가
  - RemoteDataSource에서 API 응답을 DTO 구조에 맞게 변환
- 회사 관리 API 응답 파싱 오류 수정
  - CompanyResponse의 필수 필드를 nullable로 변경
  - PaginatedResponse 구조 매핑 로직 개선
- 에러 처리 및 로깅 개선
  - Service Layer에 상세 에러 로깅 추가
  - Controller에서 에러 타입별 처리
- 새로운 유틸리티 추가
  - ResponseInterceptor: API 응답 정규화
  - DebugLogger: 디버깅 도구
  - HealthCheckService: 서버 상태 확인
- 문서화
  - API 통합 테스트 가이드
  - 에러 분석 보고서
  - 리팩토링 계획서

lib/data/models/warehouse/warehouse_dto.g.dart

@@ -65,17 +65,21 @@ _$WarehouseLocationDtoImpl _$$WarehouseLocationDtoImplFromJson(
     _$WarehouseLocationDtoImpl(
       id: (json['id'] as num).toInt(),
       name: json['name'] as String,
+      code: json['code'] as String?,
+      managerName: json['manager_name'] as String?,
+      managerPhone: json['manager_phone'] as String?,
+      capacity: (json['capacity'] as num?)?.toInt(),
+      isActive: json['is_active'] as bool,
+      createdAt: DateTime.parse(json['created_at'] as String),
       address: json['address'] as String?,
       city: json['city'] as String?,
       state: json['state'] as String?,
       postalCode: json['postal_code'] as String?,
       country: json['country'] as String?,
-      capacity: (json['capacity'] as num?)?.toInt(),
       managerId: (json['manager_id'] as num?)?.toInt(),
-      managerName: json['manager_name'] as String?,
-      isActive: json['is_active'] as bool,
-      createdAt: DateTime.parse(json['created_at'] as String),
-      updatedAt: DateTime.parse(json['updated_at'] as String),
+      updatedAt: json['updated_at'] == null
+          ? null
+          : DateTime.parse(json['updated_at'] as String),
       currentStock: (json['current_stock'] as num?)?.toInt(),
       availableCapacity: (json['available_capacity'] as num?)?.toInt(),
     );
@@ -85,17 +89,19 @@ Map<String, dynamic> _$$WarehouseLocationDtoImplToJson(
     <String, dynamic>{
       'id': instance.id,
       'name': instance.name,
+      'code': instance.code,
+      'manager_name': instance.managerName,
+      'manager_phone': instance.managerPhone,
+      'capacity': instance.capacity,
+      'is_active': instance.isActive,
+      'created_at': instance.createdAt.toIso8601String(),
       'address': instance.address,
       'city': instance.city,
       'state': instance.state,
       'postal_code': instance.postalCode,
       'country': instance.country,
-      'capacity': instance.capacity,
       'manager_id': instance.managerId,
-      'manager_name': instance.managerName,
-      'is_active': instance.isActive,
-      'created_at': instance.createdAt.toIso8601String(),
-      'updated_at': instance.updatedAt.toIso8601String(),
+      'updated_at': instance.updatedAt?.toIso8601String(),
       'current_stock': instance.currentStock,
       'available_capacity': instance.availableCapacity,
     };