feat(nui): Allow DUI Keyboard Input

[Mycroft-Studios]

Goal of this PR

A better version of: PR #2195 , to add the ability to use keyboard inputs in DUI. Please See this forums post for why this ability would be very useful.

Currently keyboard inputs are: A. impossible on any external sites B. very janky and too specific (having to apply the code to each individual input) on internal UI

How is this PR achieving the goal

This PR adds 2 brand new natives: SET_DUI_KEYBOARD_INPUT - Works the same way as NUI focus, but for DUI KEYBOARD_HAS_KEYBOARD_INPUT - to check if the dui is currently focused or not

This PR applies to the following area(s)

Natives, NUI, DUI

Checklist

• [ x] Code compiles and has been tested successfully.
• [ x] Code explains itself well and/or is documented.
• [ x] My commit message explains what the changes do and what they are for.
• [ x] No extra compilation warnings are added by these changes.