Tree layout and focus direction

Hi! It's been a while, but I had a lot of personal matters that took me away from working on these features. I think this is in a good state. I've moved the binary space partition work to this branch instead, along with some additional stuff. 1. "Binary Tree" and "Spiral Tree" layouts. 2. Focus on tiles using directional input rather than "next" or "previous". I've tested these features, the layouts work fine. Currently, focus direction switching is also good, but the algorithm can be refined a bit. I can come back to that. Additionally, I'm planning to implement window swapping by direction as well, but I'll add that another time. Let me know what you think!