優化公共事業費：修正日期顯示、改善發票號碼輸入UX與調整介面欄位順序

resources/js/utils/validation.ts

@@ -70,3 +70,20 @@ export const validateWarehouse = (formData: {
 
   return { isValid: true };
 };
+
+/**
+ * 驗證發票號碼格式 (AA-12345678)
+ */
+export const validateInvoiceNumber = (invoiceNumber?: string): { isValid: boolean; error?: string } => {
+  if (!invoiceNumber) return { isValid: true };
+
+  const regex = /^[A-Z]{2}-\d{8}$/;
+  if (!regex.test(invoiceNumber)) {
+    return {
+      isValid: false,
+      error: "發票號碼格式錯誤，應為：AB-12345678",
+    };
+  }
+
+  return { isValid: true };
+};