I want to run github-codeowners audit --unloved and have the CI fail if there are any unloved files (our policy is that every file needs an explicit owner). The same goes for running github-codeowners validate, if that finds any entries that do not exist in the file system.
The best way for this would be to set the exit code to a non-zero code so that GitHub Actions (or any other tool) recognizes that the check failed.