End-of-term xray-file retention + disposal policy (fleet)

Elazar 2026-07-18: no need to keep xray (radiografía) image files after a term/year ends. Decide the end-of-term retention + disposal policy for práctica xray files. Files live in the api-images service (Hostinger, api.pensanta.com tenant), keyed per práctica — NOT Supabase. Decision needs: (1) retention window — purge at term-end vs keep N months for appeals/audit; (2) mechanism — hard-delete from api-images vs archive-to-cold (gdrive backup) then delete vs export-then-delete; (3) DB consistency — nulling/soft-deleting the práctica image refs when files go, with archive-context per evolutiva-db soft-delete policy; (4) who runs it — per-app term-end job vs one fleet sweep; (5) is any academic/legal hold required before deletion (grade finalization/appeal window). Cross-app (mars/pluto/venus all store práctica xrays) + db + api-images. Decision-first, no deletion until policy ratified + Elazar GO (irreversible). Relates to EVO-58 storage monitoring — term-end purge is the real long-term storage control; monitoring is the safety net.