Disable MY100 if `ty` is being used

[denialhaag]

With 2026.06.18, the PC140 check also accepts ty. However, the MY100 check still fails if a repository is using ty instead of mypy. We are currently ignoring MY100 for that reason. Would it be possible to disable MY100 from the get-go if PC140 detects that ty is being used? 🤔

[henryiii]

Yes, that's an oversight. I'm not quite sure the best way to handle the other type checkers for the MY family - if we can map them to ty/pyrefly options, that would probably be best.