fix: use getApiErrorMessage in CheckoutPage for user-friendly error display

client/src/pages/checkout/ui/CheckoutPage.tsx

@@ -21,6 +21,7 @@ import { createOrder } from '@/entities/order/api/order-api'
 import { fetchMyAddresses } from '@/entities/user/api/address-api'
 import { DELIVERY_CARRIER_OPTIONS, type DeliveryCarrierCode } from '@/shared/constants/delivery-carrier'
 import { formatPriceRub } from '@/shared/lib/format-price'
+import { getApiErrorMessage } from '@/shared/lib/get-api-error-message'
 import { $user } from '@/shared/model/auth'
 
 export function CheckoutPage() {
@@ -263,7 +264,7 @@ export function CheckoutPage() {
           Создать заказ
         </Button>
 
-        {createMut.isError && <Alert severity="error">{(createMut.error as Error).message}</Alert>}
+        {createMut.isError && <Alert severity="error">{getApiErrorMessage(createMut.error)}</Alert>}
       </Stack>
     </Box>
   )