Email rail lacks cross-rail dedup of one render's alerts

2026-09-20 17:01:43Z /informes 23s: one render wrote 2 appEvents rows (52f9443f, dd6d3c28, 731ms apart), same digest 754290896, same user. Email rail sent 2 emails; hub rail deduped. Add email-rail dedup by digest+user in a short window. fn_getInformesBundle also runs on TEACHER scope (user bfe10f4a), so PLUTO-748 sizing covers teachers.