Peak-hour 53300/pool-ceiling verification sweep post-pooler-cutover (MARS-145 off-peak caveat)

Post-MARS-145 pooler cutover: the PASS:c987038 verdict was off-peak (~04:05 ART, near-zero traffic), so the Supavisor txn-pooler pool CEILING under daytime concurrency is NOT yet exercised — the 53300/too-many-connections-under-load surface is unverified. Run an appEvents 53300/ECONNREFUSED/pool-timeout sweep at tomorrow's peak-traffic window and confirm max:6 + txn-mode holds under real fan-out. Connect-path itself already clean (drain-email-outbox cron 200 roundtrip through :6543). Audit-flagged, db-mars owns.