While refactoring the code to work with the move class and adding an undo button, I needed to redo castling. I decided to be lazy and just make it so that when you castle two moves are initiated and then when you undo, it check if the last move was by a king and the start tile's distance from the end tile is greater than one, and if so, it will just undo the last two moves.

I am so happy about this lazy solution! This is so much easier!

I will soon fix some bugs, fully implement the fallen tiles feature, and then I will publish an updated build.