Session-in-progress peer-motion work, checkpointed before bisecting the
07-13/07-14 gait regression. Contains: TCP_NODELAY on game sockets (L4NET),
every-frame dense position send while moving + came-to-rest/REST send +
per-frame BT_JIT/BT_ANIM smoothness probes (mech4). bodyTargetSpeed feed
reverted to derived-velocity default. MOVER.cpp spline experiment already
reverted. NOT a fix -- a checkpoint.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
