Implement GitHub release creation in CI workflow

[bourgeoa]

Add GitHub release step after npm publish in CI workflow.

[Copilot]

Pull request overview

Adds automated GitHub Release creation to the CI workflow so that, after publishing to npm from main, the workflow also creates (or reuses) the corresponding vX.Y.Z tag and generates GitHub release notes.

Changes:

• Introduces a new github-release job that runs after npm-publish-latest.
• Uses GitHub CLI (gh) to create a release (idempotently) and generate release notes based on the package version in package.json.

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[Copilot]

The workflow supports workflow_dispatch, and npm-publish-latest can run on manual dispatch (it only checks github.ref). However, this github-release job is additionally gated to github.event_name == 'push', so manual publishes won’t create a corresponding GitHub release. Consider either removing the event_name check (so dispatch runs also create a release) or updating npm-publish-latest to also be push-only if that’s the intent.