Right now tor doesn't resolve `auto` settings when reporting them via `GETCONF`. This means the controller might need to know beforehand how tor will behave for any given `auto` setting, which might change across tor versions or even across consensuses. We should have a way to resolve `auto` settings so controllers can discover what setting tor will actually use. Implementing this could be a lot of work because I think the behavior of many `auto` values gets determined by code in the relevant subsystem rather than in a centralized place like control.c.