Blender Git Loki

Fix #29976: Carve Boolenas crasher with Solidify

Issue was caused by union policy needed to deal with cases when operand intersects
two or more intersecting meshes of another operand.

Changed this policy to run union operation only if there's actual intersection
between two meshes of the same object. Should work in general but it's still
possible to make it behave incorrect -- for example object consist of two groups
if concentric cubes which intersects each other.