debugging-ci-failures

Debugs failing GitHub Actions CI runs for PostHog PRs, commits, and branches. Use when the user asks why CI is red, mentions a failing check, GitHub Actions run, Depot runner, workflow, job, shard, flaky test, lint failure, typecheck failure, snapshot diff, migration check, generated types drift, or skills build failure. Guides read-only inspection, failure classification, smallest local reproduction with hogli, and safe reporting without rerunning CI or posting to GitHub.