feat: indicate if chat is currently muted

src/structures/Chat.js

@@ -57,6 +57,12 @@ class Chat extends Base {
          */
         this.archived = data.archive;
 
+        /**
+         * Indicates if the chat is muted or not
+         * @type {number}
+         */
+        this.isMuted = data.isMuted;
+
         /**
          * Unix timestamp for when the mute expires
          * @type {number}