How Radar's attribution to a cluster matures — candidate → corroborated → named, actors added or dropped, activity that goes quiet or comes back. Distinct from Correlated Activity, which shows each cluster's current state; this shows how it got there, one attribution run at a time.
Field of view: transitions reflect changes observed in our collection, not the ground truth of what an actor actually did — a gap here means Radar didn't see a change, not that nothing changed.