fix(cron): notify-audit-groups 500 — Date brute en param SQL

getOverdueGroups interpolait un objet Date dans un template sql`` brut
(${fourteenDaysAgo}) -> postgres-js: TypeError ERR_INVALID_ARG_TYPE
(Received an instance of Date) -> le cron des relances plantait (500),
donc aucune relance Teams/Discord. Fix: passer fourteenDaysAgo.toISOString().

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: makcimerrr

lib/db/services/groupStatuses.ts

@@ -130,7 +130,7 @@ export async function getOverdueGroups(): Promise<(typeof groupStatuses.$inferSe
         isNotNull(groupStatuses.notifiedAuditAt),
         isNull(groupStatuses.slotDate),
         isNull(groupStatuses.reminderSentAt),
-        sql`${groupStatuses.notifiedAuditAt} <= ${fourteenDaysAgo}`
+        sql`${groupStatuses.notifiedAuditAt} <= ${fourteenDaysAgo.toISOString()}`
       )
     );
 }