Fix application hang by ensuring filter state initialization and adding robustness guards

App.tsx

@@ -212,6 +212,7 @@ const App: React.FC = () => {
       sku: [],
       title: [],
       week: [],
+      stock: [],
     });
   };
 

services/dataProcessor.ts

@@ -703,7 +703,7 @@ export const mergeSalesAndAdsData = (
 
 // Helper to check stock filter
 const checkStockFilter = (sku: string, filters: string[], stockMap?: Map<string, number>): boolean => {
-    if (!filters || filters.length === 0) return true;
+    if (!filters || !Array.isArray(filters) || filters.length === 0) return true;
     if (!stockMap) return true;
 
     // Normalize SKU (remove DE/EN) to match stock map