fix(ChatRoom): send cached presence when XMPP re-connects

modules/xmpp/ChatRoom.js

 import Statistics from '../statistics/statistics';
 
 import Moderator from './moderator';
+import XmppConnection from './XmppConnection';
 
 const logger = getLogger(__filename);
 
         this.members = {};
         this.presMap = {};
         this.presHandlers = {};
+        this._removeConnListeners = [];
         this.joined = false;
         this.role = null;
         this.focusMucJid = null;
 
             preJoin.then(() => {
                 this.sendPresence(true);
+                this._removeConnListeners.push(
+                    this.connection.addEventListener(
+                        XmppConnection.Events.CONN_STATUS_CHANGED,
+                        this.onConnStatusChanged.bind(this))
+                );
                 resolve();
             });
         });
         });
     }
 
+    /**
+     * Handles Xmpp Connection status updates.
+     *
+     * @param {Strophe.Status} status - The Strophe connection status.
+     */
+    onConnStatusChanged(status) {
+        // Send cached presence when the XMPP connection is re-established.
+        if (status === XmppConnection.Status.CONNECTED) {
+            this.sendPresence();
+        }
+    }
+
     /**
      *
      * @param pres
             const timeout = setTimeout(() => onMucLeft(true), 5000);
             const eventEmitter = this.eventEmitter;
 
+            this._removeConnListeners.forEach(remove => remove());
+            this._removeConnListeners = [];
+
             /**
              *
              * @param doReject