Restructure omni services and add Chatwoot research snapshot

research/chatwoot/app/javascript/dashboard/api/notificationSubscription.js

@@ -0,0 +1,9 @@
+import ApiClient from './ApiClient';
+
+class NotificationSubscriptions extends ApiClient {
+  constructor() {
+    super('notification_subscriptions');
+  }
+}
+
+export default new NotificationSubscriptions();