Per-take per-orbit level/register/activity from local Ardour interchange stems
via the optimized build_eda. 61/61 grounded (~8min, warm cache 12-19s on the
big SET takes). 2 empties correctly flagged (Take28 0.6s, Take63 8.6s sketches);
kick orbit (d1) sub-register on all 57 active (centroid never >300Hz).