feat: Implement i18n infrastructure

frontend/translations.ts

@@ -0,0 +1,10 @@
+import { en } from './locales/en';
+import { es } from './locales/es';
+
+export const translations = {
+  en,
+  es,
+};
+
+export type Language = keyof typeof translations;
+export type TranslationStructure = typeof en;