The sign of the projected formation direction vector flips with the fracture
direction normal, which follows the well drilling direction, while the fracture
azimuth defining the dip rotation in RimFracture::transformMatrix() is only
defined mod 180 degrees. Canonicalize the formation direction against the
fracture azimuth direction before computing the dip, so a positive dip means
the formation descends toward the azimuth direction.
Restore std::abs() in calculateFormationDipFromHorizontal() so the StimPlan
model formation dip (BedDipDeg in the Asymmetric FRK export) keeps the
non-negative convention from #8877.
