v0.4.31

Dashboard focus fix: the purple "awaiting your decision" gate is now a live-frontier state — it wins focus only at the live edge once the drive has gone quiet (parked). While the drive is actively streaming, or when scrubbing back through the timeline, focus follows the running role step (carried across hand-off / gate.surfaced / reasoning frames via a new topology.laneLast), instead of bouncing to the spec gate between every role turn in a batch /design run. The gate's own node still lights from laneGate on its surfaced frame. Hermetic reducer tests added; full dashboard suite green.