for your information, I did some improvement the generation process so
the translation is made easier.
The antora.yml file contains only translatable strings (the nav thing is
still there because of upstream bug
The nav.adoc file which is the left menu is spited in multiple strings,
making it easier to translate.
As far as I know, the only remaining issue is this to improve this file
which contain way too much markup:
Build process still is in progress thanks to Adam. That's why I don't
communicate on it yet.