Implement Excel-style stock filtering with Smart Filters and Range support

components/FilterBar.tsx

@@ -15,6 +15,7 @@ interface FilterBarProps {
     sku: string[];
     title: string[];
     week: string[];
+    stock: string[];
   };
 }
 
@@ -79,6 +80,14 @@ const FilterBar: React.FC<FilterBarProps> = ({ filters, onFilterChange, options
           onChange={(v) => onFilterChange('asin', v)}
           className="flex-1"
         />
+        <MultiSelectDropdown
+          label="Stock"
+          selected={filters.stock}
+          options={options.stock}
+          onChange={(v) => onFilterChange('stock', v)}
+          className="flex-1"
+          enableRangeSelect={true}
+        />
       </div>
     </div>
   );