Update dashboard to refresh DLC products and stats when store changes

Import `useQueryClient` from `@tanstack/react-query` and add a `useEffect` hook to invalidate `/api/dlc-products` and `/api/dlc-products/stats` queries when `selectedStoreId` changes.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 1e4433b5-47ab-464c-b663-fea2e53367dd
Replit-Commit-Checkpoint-Type: intermediate_checkpoint
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/1957c339-2757-4d1f-8e92-e9f71a1ce58e/1e4433b5-47ab-464c-b663-fea2e53367dd/Q8UjAXl

client/src/pages/Dashboard.tsx

@@ -1,5 +1,5 @@
 import { useState, useEffect } from "react";
-import { useQuery } from "@tanstack/react-query";
+import { useQuery, useQueryClient } from "@tanstack/react-query";
 import { useAuthUnified } from "@/hooks/useAuthUnified";
 import { useStore } from "@/contexts/StoreContext";
 import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "@/components/ui/card";
@@ -15,9 +15,16 @@ import { DlcAlertModal } from "@/components/DlcAlertModal";
 export default function Dashboard() {
   const { user } = useAuthUnified();
   const { selectedStoreId } = useStore();
+  const queryClient = useQueryClient();
   const [showAnnouncementModal, setShowAnnouncementModal] = useState(false);
   const [showDlcAlertModal, setShowDlcAlertModal] = useState(false);
 
+  // Invalider les queries DLC quand le magasin change
+  useEffect(() => {
+    queryClient.invalidateQueries({ queryKey: ["/api/dlc-products"] });
+    queryClient.invalidateQueries({ queryKey: ["/api/dlc-products/stats"] });
+  }, [selectedStoreId, queryClient]);
+
   const { data: stats } = useQuery({
     queryKey: ['/api/stats/monthly', selectedStoreId],
     queryFn: async () => {