The shadow report was a desync symptom, not a bias/tilt bug: the ~2-4 unit
depth-bias margin is tight enough that v4's out-of-phase leg pose showing
through could push the flat quad under a slope. No shadow code changed;
both symptoms cleared together. Noted as a diagnostic hint (check
[sync]/BT_SYNC_LOG before touching bias/tilt for this report class).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
