결재 및 마스터 모듈을 v4 API 계약에 맞게 조정

lib/features/masters/customer/data/dtos/customer_dto.dart

@@ -9,6 +9,7 @@ class CustomerDto {
     this.id,
     required this.customerCode,
     required this.customerName,
+    this.contactName,
     this.isPartner = false,
     this.isGeneral = true,
     this.email,
@@ -25,6 +26,7 @@ class CustomerDto {
   final int? id;
   final String customerCode;
   final String customerName;
+  final String? contactName;
   final bool isPartner;
   final bool isGeneral;
   final String? email;
@@ -43,6 +45,7 @@ class CustomerDto {
       id: json['id'] as int?,
       customerCode: json['customer_code'] as String,
       customerName: json['customer_name'] as String,
+      contactName: json['contact_name'] as String?,
       isPartner: (json['is_partner'] as bool?) ?? false,
       isGeneral: (json['is_general'] as bool?) ?? true,
       email: json['email'] as String?,
@@ -65,6 +68,7 @@ class CustomerDto {
       if (id != null) 'id': id,
       'customer_code': customerCode,
       'customer_name': customerName,
+      'contact_name': contactName,
       'is_partner': isPartner,
       'is_general': isGeneral,
       'email': email,
@@ -84,6 +88,7 @@ class CustomerDto {
     id: id,
     customerCode: customerCode,
     customerName: customerName,
+    contactName: contactName,
     isPartner: isPartner,
     isGeneral: isGeneral,
     email: email,