Typescript migration:

* Refactoring of scheduler and jobs to use promises.
* Add "failed" state for tasks.

server/jobs/OfflineNodesDeletionJob.ts

@@ -0,0 +1,20 @@
+import MonitoringService from "../services/monitoringService";
+import Logger from "../logger";
+
+export default {
+    name: 'OfflineNodesDeletionJob',
+    description: 'Delete nodes that are offline for more than 100 days.',
+
+    run: (): Promise<void> => {
+        return new Promise<void>((resolve, reject) => {
+            MonitoringService.deleteOfflineNodes((err: any): void => {
+                if (err) {
+                    Logger.tag('nodes', 'delete-offline').error('Error deleting offline nodes:', err);
+                    return reject(err);
+                }
+
+                resolve();
+            });
+        });
+    }
+};