Write & POST May 28 standup to Slack (12:30-13:30 UTC window) — Sergey SSO gap + cleanup residue

Daily standup task per LEARNINGS 2026-05-28 04:10 UTC reflection and AGENTS.md End-of-Reflection Wiring Audit item (3). Posting window: 2026-05-28 12:30-13:30 UTC. DoD: Slack DM to Carson (channel D0B0980TR88) + memory/standups/2026-05-28.md. MANDATORY final-refresh step before send: re-read fleet-task resume, latest Slack DM/assistant-thread messages since 2026-05-27 13:36 UTC, latest PR truth for #11190/#11191/#11198/#10870/#11189 and older backlog (#9886/#9932/#9353/#10401/#10498/#10499/#10508/#10824), active-ci-watch.env, and any new auth/identity work Carson started. Patch memory/standups/2026-05-28.md so no stale claim survives. In particular, do not imply #11190 is still open/superseded if it was closed/merged, and do not present the Sergey SSO membership branch as approved implementation unless Carson explicitly approved it. Content draft: May 27 standup posted inside window; Sergey SSO investigation found the existing-user-not-org-member gap after correcting an old-RDS query mistake; #11190 remains a cleanup decision at draft time; active-ci-watch.env is stale for merged #11191; older backlog remains hold/report-only unless truth changed. Include the Sergey SSO membership-gap decision prompt and #11190 cleanup prompt unless Carson already answered them before send. Send-side timing/status guard: do not send before metadata.trigger_after_utc or 12:30 UTC. If task is leased early, renew/checkpoint or leave queued rather than waiting silently past the 5-minute lease. After successful Slack send, immediately PATCH this task to completed with slack_ts, delivered_at, and memory_file before any other work. Topic for ping-lockout bookkeeping: standup-2026-05-28. CHECKLIST-CONTACT Gates 1-8 must run before send. Pre-staged body path: memory/standups/2026-05-28.md