add-language

# Adding a new interface language The app bundles translations at build time. Adding a locale means touching five code locations plus two prose locations. Miss any one and the failure is silent: i18next falls back to English mid-screen, or the new locale ships with no key-parity coverage. Run all npm commands from `app/`. Below, `{code}` is the ISO code (`it`) and `{Name}` is the language's own name for itself (`Italiano`). ## 1. Create the translation file ```bash mkdir -p app/src/locales/{code} cp app/src/locales/en/translation.json app/src/locales/{code}/translation.json ``` ## 2. Translate the values Translate every value in `app/src/locales/{code}/translation.json`. Do not change, add, or drop keys. The key-parity test in step 5 fails if the shape drifts from `en`. Labels must fit 320px (project rule in `AGENTS.project.md`), so prefer the concise translation where two options exist. ## 3. Add the language name to every translation file The `languages` section of each locale lists all languages, so the picker reads correctly whatever language the UI is currently in. Add `"{code}": "{Name}"` to the `languages` section of every `translation.json` under `app/src/locales/`, the new one included. List them first rather than working from memory: ```bash ls app/src/locales ``` Use the same string `{Name}` in all of them. Language names are not translated. ## 4. Register the locale in i18n In `app/src/i18n.ts`, add the import alongside the others and the entry in `r...