cross method
Implementation
UArVector3 cross(UArVector3 other) => UArVector3(y * other.z - z * other.y, z * other.x - x * other.z, x * other.y - y * other.x);
UArVector3 cross(UArVector3 other) => UArVector3(y * other.z - z * other.y, z * other.x - x * other.z, x * other.y - y * other.x);