/spin

CMDBOOK-2228 - Reported by sharqman

like /slap except it turns the player 90 degrees with no other movements, can enter in a number to turn them multiple times. This will be very useful to get players to look the right way, for example when spawn can only face south, you can have a script block to /spin them to the right direction.

Start by locating the existing /slap command and its command registration, then compare how it applies movement to a player. Implement /spin so it rotates the player 90 degrees per invocation, accepts an optional number of turns, and performs no other movement. Verify that the player faces the requested direction, including the spawn-orientation use case.

Written by the indexing model from the issue text.