AetherDrive.cs: master deleted the behaviour (2cfdc728); the branch only added a
TurnRate line to it. Deletion kept. Thruster remains the one rotation actuator
and feeds Entity.TurnRate. No sim stepping outside the clock on master
(mines presenter, Pirates AI, lot-product all step through Zone.Update).
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>