ci: bump checkout to v5 and add all-checks-passed gate

[jnasbyupgrade]

Small CI-hygiene change, independent of the larger test-capabilities work.

• actions/checkout@v4 → v5 — v4 emits a Node 20 deprecation warning on current runners.
• all-checks-passed aggregation job — one stable required-status-check name for branch protection, instead of the matrix-dependent 🐘 PostgreSQL <n> names. Passes if every needed job succeeded or was skipped; fails if any failed/cancelled.

No change to what's tested (still pg-build-test across the PG 9.3–17 matrix). Follow-up PRs will add the pg_upgrade and pg_tle jobs.

🤖 Generated with Claude Code

[coderabbitai]

Important

Review skipped

Auto reviews are disabled on this repository. Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro Plus

Run ID: 8a27d535-e939-4171-aa96-e96b10181916

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

• 🔍 Trigger review

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}