QA staging Postgres 16 upgrade

[luandro]

Goal

QA the environment (Postgres 17.5) to validate the upgrade path and unblock the production rollout.

References

• QA Verification Script
• Smoke Test Checklist
• Heroku Environment Snapshot
• DB Upgrade Plan
• Config Sync Helper
• Related PR: docs: capture pg17 staging rehearsal #1008

Related Work

• Upgrade Postgres from 14 to 17 #1005 – Upgrade Postgres from 14 to 17 (production follow-up once PG17 staging QA is green).
• Upgrade Ruby (and likely gem deps) #1004 – Upgrade Ruby (and gem deps) to align with the Heroku-24 stack validated during this QA.

Tasks

• Run the environment snapshot + verification steps in against , recording outputs (rowcounts, test logs, screenshots).
• Execute the smoke checklist in for the PG17 staging app post-tests.
• Log any failures/regressions as follow-up issues and update with new release metadata if changes occur (ensure no secrets).
• Confirm rollback readiness per after QA completes.

Notes

Do not modify live production config or secrets during QA; all commands referenced are read-only or limited to staging apps ( / ).