PostureComponent gains bEnableBodyTracking flag. When false, only
head and eyes track the target — body stays frozen.
InteractionComponent now:
- On posture attach: sets TargetActor but disables body tracking
(agent notices player with eyes+head only)
- On StartListening: enables body tracking (agent fully engages)
- On StopListening: disables body tracking
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>