Unify distance, similarity, and uncertainty instantiation

[thevolatilebit]

In CEEDesigns.GenerativeDesigns, while "distances" and "similarities" are provided by a user through a function call, an "uncertainty" is given as a type. See the following for reference:

CEEDesigns.jl/tutorials/GenerativeDesigns.jl

Lines 158 to 164 in d1d09c3

	DistanceBased(
	data[!, ["RestingBP", "MaxHR", "Cholesterol", "FastingBS", "HeartDisease"]]; # the Mahalanobis distance only works with numeric features, so we selected a few, along with the target variable
	target = "HeartDisease",
	uncertainty = Entropy,
	similarity = Exponential(; λ = 5),
	distance = MahalanobisDistance(; diagonal = 1),
	);

It may be worth unifying the style.