[LyX/master] Import Additional from 2.4.x

[jpc]

commit 18ce7a2e80060179c965c71903c2589551690d39
Author: jpc <jpc at lyx.org>
Date:   Tue Jul 9 18:15:48 2024 +0200

                Import Additional from 2.4.x

 lib/doc/fr/Additional.lyx | 3871 ++++++++++++++++++++++++++-------------------
 1 file changed, 2236 insertions(+), 1635 deletions(-)