Frames of one mount are the same loop seen again, so the paired bootstrap now draws
mounts (data/gold/groups.json, built by tools/gold_groups.py from the mount ids the
studio writes in the gold manifest). The comparison also reports the unseen core without
the saturated frames, and frames the studio dropped from the gold set are pruned.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
