Added French Language Support

Serving French-speaking audiences used to mean a separate localisation project. French is now available as a full supported language in Basker. The language picker and middleware keep locale state current as editors move between previews and languages, so switching from English to French mid-session does not leave stale interface strings or broken preview context.

What is covered

French support includes CMS labels, content locale handling, preview state, and runtime language switching. For organisations publishing across regions or serving bilingual audiences, localisation is now part of the normal editing workflow rather than a separate development project.

Foundation for future languages

The same locale infrastructure underpins future language additions. Supporting a new language requires labels, route validation, preview state, date formatting, and theme data to all agree before it feels reliable in production. That infrastructure is now in place.