Consistently use edge draw flag instead of original index to determine if an
edge should be drawn or not.
In GPU subdivision the edge original index was used for both edge optimal
display and selection mapping to coarse edges, but they are not the same.
Now match the CPU subdivision logic and use a separate edge draw flag VBO.
For cage display, match Blender 3.3 behavior more in showing/hiding of edges
in wireframe mode. That is edges without a mapping to an original edge are
always hidden when there is no distinct cage, and drawn otherwise. This is
not ideal for e.g. the bevl modifier where it will always show some edges on
corners despite all edges being hidden by the user. But we currently have
no good information to decide if these should be hidden or not, so err on
the side of showing too much as it did before.
Fie #103706: bevel modifier edges not drawn correctly
Fix#103700: optimal display can't be turned of with GPU subdivision
Fix wrong edge display with GPU subdivision preceded by other modifiers
Brecht Van Lommel