Implement IHoldable, VrPlayerHand, very much a WIP
Simplify InGrip, InTrigger - simulate input to drop held entity if we can.
Delete FocusWorldPanel, it's unused
Set up client preferences system
Clients save the data as a cookie. When the game starts up the client informs the server of their preferences. Ideally this'll be good for flipping the paddle hand, changing the paddle angle and adjusting the VR anchor.
Work on ClientPreferencesWidget
Set up WorldInput ray
Gut out the ServeHand so stuff still compiles