Maybe this is final, unless someone sees a need to make this more formal (or in TypeScript).
One bug found/fiixed. Also made the sliders work for all three axes. For each axis, the centerline of the wedge is on that axis with wedge angles specified as Left Hand Rule (aka counter-clockwise/leftward when looking outward from 0,0,0) around that axis. An angle of zero is facing the “previous” axis.
Note that the axes display disappears if the final result is an empty mesh. It will reappear when the wedge itself does.