feat(F-194): completed feature

project/apps/pos/src/components/PaymentModal.tsx

@@ -3,6 +3,7 @@
 import { useMemo, useState } from 'react';
 import { formatPrice } from '@/lib/money';
 import type { PaymentAllocation, PaymentMethod } from '@/types/checkout';
+import { generateIdempotencyKey } from '@/lib/idempotency';
 
 interface PaymentModalProps {
   method: PaymentMethod;
@@ -48,7 +49,7 @@ export default function PaymentModal({
       return;
     }
     onAdd({
-      id: crypto.randomUUID(),
+      id: generateIdempotencyKey(),
       methodCode: method.code,
       methodLabel: method.label,
       kind: method.kind,