Fixed form_file_select function glitch and new Trongate MX attributes

Introduced 'mx-during-request' and 'mx-after-swap' attributes to enhance user experience in Trongate MX. The 'mx-during-request' controls the appearance of elements during AJAX requests, while 'mx-after-swap' allows executing JavaScript functions after content swaps. Refactored app.js to add a feature that closes open modals when clicking outside of them (which was surprisingly tricky!). Special thanks to our very own Godfather of Speed Coding, Dafa, for fixing the recent glitch with the form_submit() helper method. Everything's smooth and running perfectly now!

ALSO, this update includes a fix for the form_file_select() form helper function.