feat: editable new-order poll interval in admin settings

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/app/i18n/translations.ts

@@ -1959,6 +1959,10 @@ export interface Translations {
     currencyRatesExplain: string;
     currencyRatesSave: string;
     currencyRatesSaved: string;
+    notificationInterval: string;
+    notificationIntervalExplain: string;
+    notificationIntervalSave: string;
+    notificationIntervalSaved: string;
   };
   adminAnalytics: {
     topProductsEmptyTitle: string;