fix(tools): two scripts were +x on disk and 644 in the index

gig-up's "tools executable" gate has been NO-GO on this box, and the reason is
the trap the repo already has a lesson about: chmod fixes YOUR tree, not the
repo. parvagues-protect.sh and install-protect.sh both ran fine here and were
recorded 100644, so a fresh clone gets two non-executable protect scripts —
and the gate that catches it was being read as noise because it never went
green. Fixed with `git update-index --chmod=+x`, which is the half that was
skipped. lcxl-path.py (new in 7bda1ccd) had the same defect and gets the same
treatment.

Note the gate checks BOTH `-x` on disk and the index mode. Only the index half
was failing, which is exactly the failure a local chmod hides.