Fixed a bug in coordinate snap to integer for boundary edges. New code checks and eventually updates the start and end uv coordinates of the interior half edge of boundary edges instead of the exterior one and this fix a bug that causes sometimes a missing qaud face near a boundary edge.
The fix makes ReForm produce a good result in a new added test box_open.obj .Before the result had some missing face near the boundary.

[git-p4: depot-paths = "//ReForm/ReForm/main/CoMISo/": change = 11996]