Co-authored-by: Copilot copilot@github.com

Pull Request Summary

This PR introduces support for an optional pr-number input so deployments can reliably comment on the correct pull request, especially in fork-safe and workflow-run scenarios. #729

Main Changes

• Added a new optional action input: pr-number.
• Wired pr-number into shared input handling and input key constants.
• Updated pull request comment resolution logic to:
  • Prefer pr-number when provided.
  • Validate input and throw a clear error for invalid values.
  • Keep event-based fallback behavior for pull_request, workflow_dispatch, and workflow_run.
• Refactored comment resolution with stricter assertions and clearer failure cases.
• Updated documentation to explain when and why to set pr-number, especially for fork-safe workflow_run usage.
• Updated deploy workflow behavior to:
  • Trigger on pull requests targeting main.
  • Add a dedicated fork notice job.
  • Skip secret-dependent deploy steps for fork pull requests.
• Added tests for:
  • Successful PR node ID lookup via pr-number.
  • Invalid pr-number handling.
  • Updated common input shape expectations.
• Regenerated dist bundles.
• Added a changeset marking this as a minor feature release.