refactor(FE-208,212): enhance PurchaseOrderDetail and PurchaseOrderStaffApprovalForm to conditionally allow updates based on approval step

src/components/pages/purchase/form/order/PurchaseOrderStaffApprovalForm.tsx

@@ -39,7 +39,7 @@ const PurchaseOrderStaffApprovalForm = ({
     useState('');
 
   // ===== UTILITY FUNCTIONS =====
-  const canUpdatePurchase = useMemo(() => {
+  const canUpdatePurchaseItems = useMemo(() => {
     if (!initialValues?.approval) return false;
 
     const currentStep = initialValues.approval.step_number;
@@ -125,7 +125,7 @@ const PurchaseOrderStaffApprovalForm = ({
     validateOnChange: true,
     validateOnBlur: true,
     onSubmit: async (values) => {
-      if (type === 'edit' && !canUpdatePurchase) {
+      if (type === 'edit' && !canUpdatePurchaseItems) {
         setPurchaseOrderFormErrorMessage(
           'Tidak bisa diupdate. Harus melewati step 4 dahulu (Tahapan Penerimaan Produk).'
         );