Comment 1 for bug 1826504

I see a potential problem here: Since workareas can theoretically have any radius, we will need to iterate over all buildings of the player on the map to check for overlaps. That may be slow. Do we want to define a constant X so that a building with overlapping workarea will be ignored if it is further than X away from the new site?

Should we also indicate overlaps with buildings of other players if they are visible? (Useful e.g. for militarysites)