Make chat DPI aware

[alextwothousand]

The chat just becomes much too small on a 4K display, so DPI awareness would be much appreciated!

[Whoeza]

There seems to be a native for alt:V that returns the screen resolution, according to Stuyk's GitHub Pages website:

https://stuyk.github.io/altv-js-docs/client/getScreenResolution.html

So, this could be easy to implement, as a scale factor of the font size, proportional to the return value of this native.

@echoWanderer I'd like to help you, if anything with this little research. :)