Scope mapping parameters

[JacksonUtsch]

Currently Scope conforming to ReducerProtocol utilizes WritableKeyPath or CasePath as parameters for mapping. I've found a closure to be more flexible with mapping state/action from multiple parent properties or usage with optionals, nested state, etc.. There probably is a performance bump with the path usage but I'm not sure they can cover all these edge cases.

Is an alternative initializer warranted for these situations?