Fix PR Review Workflow

Workflow for addressing review comments on pull requests.

Expected Command Format

Please revise the reviews at https://github.com/{owner}/{repo}/pull/{pr_number}#pullrequestreview-{review_id} and reply to each review with your results.

Input Formats

User may provide either:

• PR number: 563, #563
• Full review URL: https://github.com/{owner}/{repo}/pull/{pr_number}#pullrequestreview-{review_id}

Extract {pr_number} (and optionally {review_id}) from the input.