#22085 Improve typing of `Subsystem` to throw error when missing `help` (and other required ClassVars) Issue created by sureshjoshi Stems from this Slack convo: https://pantsbuild.slack.com/archives/C046T6T9U/p1741350745698019 But essentially, if someone adds a new subsystem, we require that they add a

help

(as we use it during

pants help

) - but it doesn't throw a pyright or mypy error if missing. pantsbuild/pants