Center Playing Field Update — Chaste Tris Steam update #610892

For a few important reasons, I have changed the Tetris field to be in the center of the window. First, this is the way it has been done in literally every other Tetris game I have played. Second, I noticed that most preview videos on TikTok show the center of the video and not the sides. This makes all my own gameplay videos of Chaste Tris hard to tell apart. So I am correcting my previous error. Also, I added a scrolling checkerboard animation to the right of the field because it is my favorite pattern!