Move transforms do not respect requested scale order

[mwaskom]

When using a move like Stack or Dodge, the order of the levels does not change if a Nominal scale with explicit order is set for the variable. (The order of the mapping itself does change, so the plot is still correct, just maybe not what you wanted):

p = so.Plot(tips, x="time", color="smoker").add(so.Bar(), so.Hist(), so.Stack())
p

p.scale(color=so.Nominal(order=["Yes", "No"]))

This works differently in the function interface and so we probably want to have that be the default. Maybe we want to support different ordering for the move and the mapping? See also #2888

I believe this is a relatively easy fix because of our internal Groupby object with custom ordering logic. But the exact sequence of operations is a little bit unclear — will we always have the scale set up by the time we need to know the order of transform application?