Write & POST June 6 standup to Slack (12:30-13:30 UTC window) — #11695 merged + #11789 DeepSource-blocked

Post the June 6 standup to Carson Slack DM (target D0B0980TR88) in the 12:30-13:30 UTC window. Body pre-staged at memory/standups/2026-06-06.md. Mandatory step (0): eval "$(~/bin/gh-fleet-token.sh)" as an isolated standalone-line shell statement, then verify ${#GH_TOKEN}==40 on the next line. Mandatory final-refresh step: run `gh pr view 11789 --json state,reviewDecision,mergeStateStatus,mergedAt,statusCheckRollup` + `gh pr view 11695 --json state,mergedAt` and re-verify the older backlog summary; update the pre-staged body in place if anything changed. Send-side timing/status guard: do NOT post before 2026-06-06T12:30:00Z; if leased earlier, renew/checkpoint until trigger window. Post-push duplicate-suppression gate (AGENTS.md lines 93+ + POST-PUSH-PROTOCOL.md Phase 5): read last 25 Carson DMs to confirm no duplicate same-topic ping in last 24h (the 2026-06-05 23:40 UTC DeepSource ping is the same-topic; this standup is the routine scheduled standup, not a duplicate, but the body must not just re-paste it). Atomic completion: PATCH this task to completed with metadata.slack_ts, memory_file, delivered_at immediately after Slack delivery in the same execution path.