[FEAT] Helper function: make modal

[aclist]

Browser

Firefox-based

Script manager

Tampermonkey

KES version

4.3.0-beta.33

Describe the feature

While refactoring the softblock mod to make a cleaner menu, I'm finding I have to basically reimplement a modal logic like the one used by MES. A function should be available to easily set up a generic modal with Mbin styling pre-applied and basic show/hide functionality. Mods could add elements into this canvas and call simple methods on it.

[aclist]

This is now provided by https://github.com/aclist/kbin-kes/pull/468