Internationalization

Pages default to English (en-US). Member exposes English, 简体中文 (zh-CN) and 日本語 (ja-JP). A saved supported choice in vh5:locale takes precedence on startup; <html lang> updates. The five documentation locales are separate from the three app switcher options.

Shared page copy is in packages/locales/src/langs/{en-US,zh-CN,ja-JP}/{app,mobile,demo}.json. Keep key sets aligned, including accessibility labels, errors and route titles. Existing zh-TW dictionaries remain for custom integration but do not contain all new mobile/demo keys and are not in the default selector.

Each app's src/locales/index.ts loads app messages and native UI language packs. NutUI uses the local nutui-ja.ts adapter for Japanese; Varlet registers then selects locale; Vant loads its locale pack. Use useI18n() in shared components, and t from @/locales in app components.

await loadLocaleMessages('ja-JP') switches language. It loads shared/app/native messages before applying the choice; English is the shared fallback. To add a language, update the supported type, messages, persistence allowlist, LanguageSelect, native adapters and tests together.

REST and AI requests send Accept-Language. Nitro localizes product fixtures; real backend and AI content remain the backend's responsibility. Query keys include locale. Do not remove i18n files alone: shared pages and Query hooks depend on the locale package.