tools: add org-wide CI status report

[evenstensberg]

Hi! Implemented this in webpack to better improve our CI's while having overview that most of our repositories are healthy. Thought it is useful for node as well. I know there's probably a lot of changes needing to be iterated on, e.g documentation of this script + symlinking or similar. Happy to re-iterate until it's good enough to be useful for you.

AI description 👇🏽

Add a script that reports the CI health of every repository in a GitHub organisation on its default branch, so the state of the whole org can be seen at a glance instead of opening each repository in turn.

The checks are deliberately conservative: a repository is only reported green when that could actually be verified. API errors, truncated check-run pages, conclusions the script does not model, and commits that active workflows never ran on are all reported as unverified rather than rounded up to a pass. Dependabot "dynamic/" runs are excluded by default since they are not the project's own CI, superseded check runs and workflow runs are collapsed to the newest attempt, and every request is pinned to the head SHA resolved up front so a push landing mid-scan cannot mix results from two commits.

Repositories are scanned in parallel with each worker writing its own result file, so the closing summary is computed from complete data and a worker that dies is counted as unverified instead of disappearing. Behaviour is tunable through ORG, INCLUDE_ARCHIVED, INCLUDE_FORKS, CANCELLED_IS_FAIL, INCLUDE_DYNAMIC_RUNS, JOBS and REPO_LIMIT; the exit status is 0 only when every scanned repository was verified green.