minAmount max amount 타입 변경 및 ars

src/pages/transaction/billing/charge-page.tsx

@@ -16,7 +16,7 @@ export const BillingChargePage = () => {
 
   const [billKey, setBillKey] = useState<string>('BIKYvattest01m');
   const [productName, setProductName] = useState<string>('테스트상품123');
-  const [productAmount, setProductAmount] = useState<number | string>(1000000);
+  const [productAmount, setProductAmount] = useState<number>(1000000);
   const [orderNumber, setOrderNumber] = useState<string>('P146733723');
   const [buyerName, setBuyerName] = useState<string>('김테스트');
   const [paymentRequestDate, setPaymentRequestDate] = useState<string>('2025-06-08');
@@ -109,7 +109,7 @@ export const BillingChargePage = () => {
                     <input 
                       type="text" 
                       value={ productAmount }
-                      onChange={ (e: ChangeEvent<HTMLInputElement>) => setProductAmount(e.target.value) }
+                      onChange={ (e: ChangeEvent<HTMLInputElement>) => setProductAmount(parseInt(e.target.value)) }
                     />
                   </div>
                 </div>