A.19.CHR:4.8.2 - Variant — archive retention with report-only illumination

For an Archive-mode use, retain the selected set under the explicitly selected selector policy. The two-offer case can retain {A,B}; archive maintenance requires its own admitted policy and declarations. Record the exact DescriptorMap and DistanceDef editions when computing illumination, together with the policy declaring that result report-only. A separate CAL policy is required before illumination influences dominance. An archive label, descriptor display or diversity summary cannot silently change the comparison or discard either offer.