When building a net tie, all elements in the footprint that belong to
the net tie can be arbitrarily close to one another. outside of the
footprint, connected items can be arbitrarily close to the tie element
but must respect the clearance values for elements that have nets
assigned to them
Fixes https://gitlab.com/kicad/code/kicad/-/issues/19933
(cherry picked from commit bff819edb0)