A simple scene manager system akin to Unity or Godot. Each scene gets to be entirely independent and does not need to know other about other scenes' broadcasts. Only the scene's controller needs to know about "Scene.[Something]" broadcasts. Press 2 to switch when on scene 1, and 1 to switch when on scene 2. Mostly just shared to be able to backpack it myself. The input system isn't entirely figured out--I'm not sure if it should be a global thing or a scene-specific thing. It probably depends on the game.
