사용자 테넌트 소속 데이터 정리

userfront/lib/features/auth/presentation/signup_screen.dart

@@ -333,7 +333,7 @@ class _SignupScreenState extends State<SignupScreen> {
         name: _nameController.text.trim(),
         phone: _phoneController.text.trim(),
         affiliationType: _affiliationType,
-        companyCode: _affiliationType == 'AFFILIATE' ? _companyCode : null,
+        tenantSlug: _affiliationType == 'AFFILIATE' ? _companyCode : null,
         department: _deptController.text.trim(),
         termsAccepted: true,
       );