[Enhancement] Port to GTK4

[Xpl0itU]

This will give a more modern look to the program, #12 is an incomplete attempt at doing so, so it can be used as a reference

[Impeta]

Why not Qt instead?

[Xpl0itU]

I've used Qt before and I've come to the conclusion that I don't like Qt

[necromancerkirby]

I would also vouch for Qt. Outside of its UI toolkit it has a very useful framework for queuing/downloading/JSON/etc etc a lot of it very tested.

But up to you. I'm willing to put my spare time if there's any consideration having worked on QML/QWidgets fork the project and work on a qt implementation for the UI. I've been looking into reverse engineering the wii u helper for a while but looks like you folks already done it so happy for that and happy to contribute if I can in some way.