Post title not saving

I think the problem lies here,

 $('.inside input').on('click', function() { 
    if ($(this).is(':checked')) {

            $('#title').val('overview');
        } else {
            $('#title').val(title);
        }
    }); 

“.inside input” in your javascript code is checkbox?
If yes then, it will also apply to publish button.
So when you click publish button,above js will be called and will change the title.
Use some id or specific class other than “.inside”.