How do you use it with i18n and theming and templates? Do you define all of these outside of typst and (e.g.) add a shadow file to the typst compiler?

Asking because I've recenly been doing something similar, but since my typst files are templates, which with the same inputs can differ and may need different translations as well, I've written a small i18n library in typst (but I guess you could require a set of translations to be present with a given typst file as well).