added indexes to system notification model

Author: appinteractive

server/models/system-notifications.model.js

@@ -5,14 +5,14 @@
 module.exports = function (app) {
   const mongooseClient = app.get('mongooseClient');
   const systemNotifications = new mongooseClient.Schema({
-    type: { type: String, default: 'info' },
-    title: { type: String },
-    content: { type: String },
-    slot: { type: String },
-    language: { type: String },
+    type: { type: String, default: 'info', required: true, index: true },
+    title: { type: String, required: true },
+    content: { type: String, required: true },
+    slot: { type: String, required: true, index: true },
+    language: { type: String, required: true, index: true },
     permanent: { type: Boolean, default: false },
     requireConfirmation: { type: Boolean, default: false },
-    active: { type: Boolean, default: true },
+    active: { type: Boolean, default: true, index: true },
     totalCount: { type: Number, default: 0 },
     createdAt: { type: Date, default: Date.now },
     updatedAt: { type: Date, default: Date.now },