Changed rock check to a general check if is near or inside any object on the world layer with limited exceptions. This restricts some spawn positions but should prevent any zombies spawning inside rocks, foundations, sealed areas of monuments, etc.
Moved junkyard spawn position to just outside as the new spawn point condition prevents hordes from spawning on the junkyard
When spawning new members into a horde, if unable to find a valid spawn point near the horde and the horde already has members bypass spawn restrictions and spawn randomly on a 1m offset from another member since we can assume they are in a valid position
Fixed incorrect number of hordes being initially spawned