chore: migrate from semantic-release to release-please

[jwulf]

Summary

Replace semantic-release (npm) with release-please (GitHub Action) for automated versioning and publishing. This eliminates 5 npm devDependencies (~170 transitive packages) and simplifies the release pipeline.

Background

We are switching to standard semver (major locked to server minor). The custom server:/server-major: commit types are no longer needed. release-please supports standard conventional commits natively with zero local dependencies.

Changes required

1. Add release-please config

Create release-please-config.json:

{
  "release-type": "node",
  "prerelease": true,
  "prerelease-type": "alpha",
  "include-component-in-tag": false,
  "packages": { ".": {} }
}

Create .release-please-manifest.json with the current version.

2. Rewrite release workflow

Replace the current release.yml with a single workflow that:

1. Job 1: Generate + test + commit drift (existing logic)
2. Job 2 (needs Job 1): Run googleapis/release-please-action@v4
   • If releasable commits exist → opens/updates a release PR → gh pr merge --auto --squash
   • If merged release PR detected → release_created=true → npm publish with OIDC provenance

Requires a PAT or GitHub App token (stored as RELEASE_PAT secret) so that PR merge triggers the next workflow run.

3. Handle stable/* branches

Use target-branch: ${{ github.ref_name }} to support both main (alpha prereleases) and stable/* (stable releases). On stable/* branches, set "prerelease": false in the config (or override via branch-specific config).

4. Remove old release tooling

• Delete release.config.cjs
• Delete scripts/next-version.mjs
• Remove from package.json devDependencies:
  • semantic-release
  • @semantic-release/changelog
  • @semantic-release/exec
  • @semantic-release/git
• Optionally remove commitlint.config.cjs, @commitlint/cli, @commitlint/config-conventional (keep if commit linting is still desired in CI)

5. Keep existing functionality

• CHANGELOG.md generation (built into release-please)
• GitHub Release creation with source tarball
• npm publish with OIDC provenance
• Docs deployment on main
• Spec snapshot archival

Considerations

• PAT requirement: GITHUB_TOKEN events don't trigger workflows. A fine-grained PAT or GitHub App token (scoped to this repo, contents: write + pull-requests: write) is needed for auto-merge to trigger the publish run.
• Latency: Similar to current flow. Push → PR updated (~30s) → CI → auto-merge → publish.
• Generated code drift: Must be committed before release-please runs. Keep drift commit in Job 1, release-please in Job 2.
• Issue success comments: Current @semantic-release/github leaves comments on referenced issues. This feature is lost (minor).