correction-apply UPDATE does not bump practicas.updatedAt

approveCorrectionRequest applies the práctica mutation + writes practicasArchive with correct actor/reason, but leaves practicas.updatedAt stale (verified: sede flipped 9→11 at 10:04:07, archive row correct, but updatedAt still 2026-07-05 16:16). Any UI/report using practicas.updatedAt as last-modified shows stale time. Fix: set updatedAt=now() in the correction-apply write path like other práctica writes. Reversible, single-path. From db-venus end-to-end verify of VENUS-168 test.