feat(frontend/api): i18n support

src/context/LanguageContext.tsx

@@ -0,0 +1,15 @@
+import React, { ReactNode } from 'react';
+
+export type AvailableLocales = 'en' | 'ja';
+
+interface LanguageContextProps {
+  locale: AvailableLocales;
+  children: (locale: string) => ReactNode;
+  setLocale?: React.Dispatch<React.SetStateAction<AvailableLocales>>;
+}
+
+export const LanguageContext = React.createContext<
+  Omit<LanguageContextProps, 'children'>
+>({
+  locale: 'en',
+});