Register src/features/comparison as the Comparison Engine UI path and wire its
extension points: the Engines popup entry, the Client Info Compare tab (A/B
selection, score delta over comparable sources, change counts, source table),
the Work Change facet before Source: Scan (only after the tab loaded a
comparison of the open timeslot) and a collapsed Finding Reader Compare
section with both states and the retained GPO values side by side. The engine
now carries those values. The Data Flow diagram shows the engine; product
version 2.26.0.
Separate new from regressed scanner deviations and accept a timeslot without
scanner runs on one side. Pair rolled-up GPO Work verdicts by scope and
technical identity with a newer backup set and the same baselines; a changed
value of a still deviating setting stays neutral. compareTimeslots yields the
change categories for the UI and a score delta over comparable sources only.