ci: key PR concurrency groups by PR number, not ref

[ccf-lisa]

When release-please merges its PR it relabels it (autorelease: tagged). That labeled event fires pull_request workflows, and for a closed/merged PR GitHub sets github.ref to the base branch (refs/heads/main), not refs/pull/N/merge. A github.ref-keyed group with cancel-in-progress then cancels the in-flight push-to-main run: this repo's own ci (push-to-main runs cancelled 2026-10-08 at 14:28, 21:24 and 21:36), and the documented preview.yml caller (mock-plugin-1 run 37850525371: "higher priority waiting request for preview-refs/heads/main").

Fix: key PR runs by PR number, keep the ref for push events:
group: <name>-${{ github.event.pull_request.number || github.ref }}. cancel-in-progress is unchanged.

• .github/workflows/ci.yml: ci-${{ github.event.pull_request.number || github.ref }}.
• README.md: preview caller snippet now uses preview-${{ github.event.pull_request.number || github.ref }}, with a one-line comment on why.

A repo-wide grep (README, docs/, .github/) found no other github.ref-keyed concurrency group; the rest use fixed names or github.repository.

No reusable workflow changes, so ci: and no release. Consuming repos' preview.yml callers need the same one-line change separately.

Checks: actionlint v1.7.12, go test -race ./..., go vet ./..., gofmt -l ., go run ./cmd/manifest on both manifests.

Task: W1-S3-FIX-CONCURRENCY (local-dev/docs/release-automation/workstream-1-foundations.md)

🤖 Generated with Claude Code

[coderabbitai]

Important

Review skipped

Bot user detected.

To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

• Configuration used: Organization UI
• Review profile: ASSERTIVE
• Plan: Advanced
• Run ID: e4791d3a-460c-488a-818a-39184c9a4649

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

• Autopilot · Keep fixing CodeRabbit findings and required CI, and resolving merge conflicts

---

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.}

[gusfcarvalho]

Reviewed: LGTM. Fixes the push-to-main CI cancellations on this repo (21:36, 21:24 and 14:28 on 2026-10-08). Events on a merged PR, like release-please's relabel, carry github.ref=refs/heads/main, so they shared main's ci group and cancelled its run. Keying the group by PR number keeps them apart, and cancel-in-progress is unchanged. The README preview snippet now matches the fix already merged on the 7 mock preview callers. ci / required is green on 8d4ee0f, and the ci: type means no release is needed.