Only use unique study day values in animation

[jwildfire]

Create a (optional?) custom tween that only transitions between unique study day values.

[jwildfire]

This still might be worth considering, but I don't think it's urgent (or even necessarily optimal). Marking low priority and bumping from v1.1.

I think the main use case where this would add a lot of value would be for very long studies with only a few visits ...