refactor: 회사 폼 UI 개선 및 코드 정리

- 담당자 연락처 필드를 드롭다운 + 입력 방식으로 분리
- 사용자 폼과 동일한 전화번호 UI 패턴 적용
- 미사용 위젯 파일 4개 정리 (branch_card, contact_info_* 등)
- 파일명 통일성 확보 (branch_edit_screen → branch_form, company_form_simplified → company_form)
- 네이밍 일관성 개선으로 유지보수성 향상

lib/domain/usecases/warehouse_location/create_warehouse_location_usecase.dart

@@ -38,7 +38,7 @@ class CreateWarehouseLocationUseCase implements UseCase<WarehouseLocationDto, Cr
       final warehouseLocation = WarehouseLocation(
         id: 0, // Default id for new warehouse location
         name: params.name,
-        address: Address.fromFullAddress(params.address),
+        address: params.address,
         remark: params.description,
       );
 
@@ -46,7 +46,7 @@ class CreateWarehouseLocationUseCase implements UseCase<WarehouseLocationDto, Cr
       return result.map((createdLocation) => WarehouseLocationDto(
         id: createdLocation.id ?? 0,
         name: createdLocation.name,
-        address: createdLocation.address.toString(),
+        address: createdLocation.address,
         isActive: true, // Default value since model doesn't have isActive
         createdAt: DateTime.now(), // Add required createdAt parameter
       ));

lib/domain/usecases/warehouse_location/update_warehouse_location_usecase.dart

@@ -46,7 +46,7 @@ class UpdateWarehouseLocationUseCase implements UseCase<WarehouseLocationDto, Up
       final warehouseLocation = WarehouseLocation(
         id: params.id,
         name: params.name ?? '',
-        address: params.address != null ? Address.fromFullAddress(params.address!) : const Address(),
+        address: params.address,
         remark: params.description,
       );
 
@@ -54,7 +54,7 @@ class UpdateWarehouseLocationUseCase implements UseCase<WarehouseLocationDto, Up
       return result.map((updatedLocation) => WarehouseLocationDto(
         id: updatedLocation.id ?? 0,
         name: updatedLocation.name,
-        address: updatedLocation.address.toString(),
+        address: updatedLocation.address,
         isActive: true, // Default value since model doesn't have isActive
         createdAt: DateTime.now(), // Add required createdAt parameter
       ));