The 18 ms gate is one game-thread tick, not compile cost (0.25 ms). MPSC handoff keeps ownership but still
polls per tick; velocity look-ahead didn't help (near -0.8 pt, p99 11.77 > 11.00). Both kept as a patch.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016dhxM43dnWvUu2B5Ph1iG1
