Locales are stored with underscores (e.g. pt_BR), but the HTML lang
attribute requires hyphens (pt-BR). Convert via a helper in the public
portal layouts.
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Co-authored-by: Sivin Varghese <64252451+iamsivin@users.noreply.github.com>