Mutating obj is CultGeometryGridEdge other && Equals(other) to && true
passed the suite: nothing exercised object.Equals directly with a mismatched
X/Y/Z/Axis, null, or an unrelated type. Add a behavioural test that checks
each component independently, rejects null and other types, and agrees with
the typed Equals and GetHashCode.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>