Add SUPPORTED_LOCALES (en, zh-CN, zh-TW, fr, es), Locale, DEFAULT_LOCALE,
isLocale, and validateLocale to @fusion/core, plus an optional
GlobalSettings.language field registered in the schema defaults and keys.
Locale primitives live in types.ts so the dashboard's @fusion/core->types.ts
Vite alias can reach them. language defaults to undefined (resolve-at-runtime).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
b8045b6f2b