fix(store): always revalidate public storefront product list

The seller store page (useGetSellerProducts) inherited the global 30s
staleTime with refetchOnWindowFocus disabled, so after a seller edited a
price the store tiles could keep showing the pre-edit price while the
(SSR) single-product page already showed the new one — a list-vs-detail
mismatch. The backend serves both from live DB and is consistent.

Set staleTime: 0 + refetchOnMount/refetchOnWindowFocus on the storefront
query so it revalidates on every visit and tab refocus, keeping the list
prices current.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/requestHandler/use-seller-hooks.ts

@@ -148,6 +148,13 @@ export const useGetSellerProducts = (
     },
     initialPageParam: 1,
     enabled: !!sellerId,
+    // Public storefront: prices/discounts must reflect the seller's latest
+    // edits. Always treat as stale and revalidate on mount/refocus so the
+    // store list can't keep showing a pre-edit price (the detail page is SSR
+    // and already fresh, which caused the list-vs-detail mismatch).
+    staleTime: 0,
+    refetchOnMount: true,
+    refetchOnWindowFocus: true,
   });
 };