Add test to Line of sight transform to check double intersections

[marcosertoli]

Describe the bug
If the LOS is crossing the edge of the machine more than once, is the intersection code getting the correct intersection, i.e. the closest to the start of the line of sight?
Depending on the choice of position & direction, it seems it doesn't always get it right.

Minimal Reproducer
Add test where the LOS originating from e.g. the LFS midplane crosses the central column and check that the intersection closest to the origin is chosen for the end point of the LOS

Same should be said for the start: it should be at the intersection of the machine dims, not further out or further in.

If behaviour is not as expected, modify intersection method.