Generate API overloads for delegate-based setups

[kzu]

We currently provide an autofix that will add the generic delegate type to the Setup<T> call,
but it would be even better if the generic argument wasn't even needed. This could be achieved
by just generating additional overloads of Setup via extension methods.

Since overload resolution is performed on parameter types (and not return value type type), there
may be chances of conflicts in generated code. Maybe in those cases the type of the delegate is
just required to disambiguate?