Two bugs caused the client to look like a bot to server GMs:
1. Strafe animation played during forward+strafe (W+A) instead of the
walk/run animation. Added pureStrafe guard so strafe animations only
play when exclusively strafing (no forward key or auto-run active).
2. CMSG_MOVE_SET_FACING was never sent on mouse-look turns. The server
predicts movement from the last known facing; without SET_FACING the
heartbeat position appeared to teleport each time the player changed
direction. Now sent at up to 10 Hz whenever facing changes >3°,
skipped while keyboard-turning (handled server-side by TURN flags).