EVO-75 mars leg: admin pending-items digest — open support tickets + access requests + correcciones to admins (Elazar)

EVO-75 (via pmmaster, not urgent, schedule AFTER EVO-79/MARS-532). Build a digest to admins (currently just Elazar) summarizing any PENDING open items: open support tickets + open access requests + pending correcciones. Reuse existing digest/cron + mailer infra (weekly-kpi/support-digest pattern). Cadence + delivery channel TBD at build (likely Vercel cron → email/outbox, honoring Hobby sub-daily cron limits). Read-only aggregation over existing tables/views; no schema change expected.