Fix TypeScript errors in AdminDashboard

frontend/src/utils/date.ts

@@ -0,0 +1,10 @@
+export function formatDate(dateString: string): string {
+  const date = new Date(dateString);
+  return date.toLocaleString('ru-RU', {
+    year: 'numeric',
+    month: 'long',
+    day: 'numeric',
+    hour: '2-digit',
+    minute: '2-digit'
+  });
+}