feat: add UI for CRON Scheduler

frontend/admin/src/App.vue

@@ -45,6 +45,10 @@
       <li :class="{active: route.name === 'logs'}">
         <RouterLink :to="{name: 'logs'}">Журнал событий</RouterLink>
       </li>
+
+      <li :class="{active: route.name === 'cron'}">
+        <RouterLink :to="{name: 'cron'}">CRON</RouterLink>
+      </li>
     </ul>
 
     <section class="form-horizontal tab-content">