This isn't so much a bug as a small issue with the way the the LiveChatAdmin.class.php is enequeing scripts. You're including the scripts in the class constructor and not via the action 'admin_enequeue_scripts'.
I noticed this issue when I activated your plugin and got the improper enqueue message from WP.
I've gone ahead and corrected the issue in my version so I wouldn't have to see message anymore while I was developing the site, but I thought I would just make sure you were aware of the issue.
Thank you, Will