Sub-ticket of MARS-349 error-digest client-noise exclusion is inert: keys on detail IS NULL, but client unhandled-errors now always carry detail{os,browser}, so the intended exclusion never matches and lone transient client 'network error' rows surface in errscan. Fix the exclusion predicate to match the intended client-noise class WITHOUT class-suppressing real client errors (design-gate, not a blind broaden). Pairs with MARS-343 forensic-capture gap. · mars