admin/usuarios:97 8-wide fan-out collapse (descoped from PLUTO-102)

Descoped from PLUTO-102 by the accepted db PLAN (2026-07-03): the 4-page collapse shipped only the 2 high/medium-ROI legs (alumnos/[id], /practicas global-oversight). admin/usuarios 8-wide + a-solucionar 6-wide were DEFERRED — LOW ROI, ZERO pool-timeout evidence (the 471 pool-exhaustion logs were /informes+/practicas only), nonzero regression risk not worth it. This is a WON'T-DO-YET capture, not active work: revisit ONLY if pool-pressure evidence appears on admin/usuarios. (a-solucionar view work is already tracked under PLUTO-101; the /practicas audit-view per-row flatten under PLUTO-483.)