fix: payment page uses USD

Keep payment page currency display fixed to USD instead of changing with selected payment method.

Made-with: Cursor

subPackages/order/payment.vue

@@ -156,13 +156,7 @@
 		return deposit.toFixed(2)
 	})
 
-	const getCurrencySymbolByMethod = (methodType) => {
+	const currencySymbol = computed(() => 'USD')
-		if (methodType === 'ALIPAY_ID') return 'Rp'
-		if (methodType === 'ALIPAY_HK') return 'HK$'
-		return '¥'
-	}
-
-	const currencySymbol = computed(() => getCurrencySymbolByMethod(selectedPaymentMethod.value))
 
 	// 加载订单信息
 	const loadOrderInfo = async () => {