Add a numerical spin up/down control to the "Construct Offset Plane"

LIke title.

The numerical spin up/down would change the offset distance with x.x.
In addition to this, please display the constructed plane position in the graphics view, while changing the offset distance value so the user can see where the plane will be constructed.

Overall, I think the constructed features could do an overhaul by displaying them in the graphics window BEFORE the user clicks "Create".