Add Catalan as a translation language

Catalan is a reasonable addition, and the proposed contributor path should work well if the locale is registered in the same way as the existing Weblate languages. I would suggest using the standard locale code ca and treating the first contribution as two separate changes:

1. Add/register the Catalan component or language in Weblate and generate the locale file.
2. Add the locale to Fluxer's language selector and fallback metadata only after the translated coverage reaches the project's threshold.

The fallback should remain the default language for missing keys, and plural rules need to use Catalan's CLDR data rather than copying a nearby Romance locale. It is also worth checking date, number, and relative-time formatting independently from translated strings. For maintainability, avoid hand-editing generated Weblate output in the application repository. Document the sync direction, required translation percentage, and how translators preview the language locally. A small smoke test that loads Catalan and verifies a few pluralized strings would catch an incomplete registration before release. If the project prefers community ownership, assigning the language to a maintainer/translator in Weblate and listing the locale's status in the release notes will make it clear when Catalan is experimental versus supported.