Investigate CI Failure

Given a PR URL (e.g. https://github.com/openshift/lightspeed-service/pull/2825), diagnose why CI jobs failed.

Workflow

1. Extract PR info

Parse org, repo, and PR number from the URL. Fetch metadata with gh:

# PR metadata
gh api repos/{org}/{repo}/pulls/{pr} --jq '{title, state, user: .user.login, head_sha: .head.sha}'

# Changed files
gh api repos/{org}/{repo}/pulls/{pr}/files --jq '.[].filename'

2. Get check statuses