fix: Filter products in admin list based on show_in_kauf and show_in_abo flags instead of billing_interval

shop/components/admin/product-list.tsx

@@ -41,9 +41,11 @@ export function ProductList({ initialProducts, categories }: { initialProducts:
 
   const filteredProducts = useMemo(() => {
     return products.filter(p => {
-      if (p.billing_interval === 'one_time') return showKauf
-      if (p.billing_interval === 'monthly') return showAbo
-      return true
+      const inKauf = p.show_in_kauf ?? true
+      const inAbo = p.show_in_abo ?? true
+      if (showKauf && inKauf) return true
+      if (showAbo && inAbo) return true
+      return false
     })
   }, [products, showKauf, showAbo])
 
@@ -134,14 +136,14 @@ export function ProductList({ initialProducts, categories }: { initialProducts:
               checked={showKauf}
               onCheckedChange={(checked) => setShowKauf(!!checked)}
             />
-            Kaufprodukte
+            In Kaufauswahl
           </label>
           <label className="flex items-center gap-2 text-sm font-medium text-slate-700 dark:text-slate-300 cursor-pointer select-none">
             <Checkbox
               checked={showAbo}
               onCheckedChange={(checked) => setShowAbo(!!checked)}
             />
-            Mietprodukte
+            In Aboauswahl
           </label>
           <Button
             variant="outline"