Review PR Skill

Review the current pull request and write the output to review.json.

Context

The working directory is the PR branch checkout.
The workflow usually provides an annotated diff in pr_diff.txt.
The workflow usually provides the PR description in pr_description.txt.
If spec_context.md exists, it contains spec context for implementation-vs-spec validation.
When the prompt references .agents/skills/review-pr/scripts/resolve_spec_context.py, use that script to materialize spec_context.md on demand instead of expecting spec content to be embedded in the prompt.
Focus on files and lines changed by this PR.
Do not post comments or reviews to GitHub directly.