Replace ajax/visibility.php and ajax/subvisibility.php by propers controllers and templates

[AdrienClairembault]

Refactor (eventually add controllers and modernize).

[AdrienClairembault]

@f2cmb I'll take this one as it is required for an ongoing PR of mine: glpi-project/glpi#23959

[f2cmb]

@f2cmb I'll take this one as it is required for an ongoing PR of mine: glpi-project/glpi#23959

i already have a PR :/ glpi-project/glpi#24065

[f2cmb]

Dunno what to do with this one @AdrienClairembault after your work