i18n by next-intl

frontend/src/navigation.ts

@@ -0,0 +1,7 @@
+import { createSharedPathnamesNavigation } from "next-intl/navigation";
+
+export const locales = ["en", "ja"] as const;
+export const localePrefix = "always";
+
+export const { Link, redirect, usePathname, useRouter } =
+  createSharedPathnamesNavigation({ locales, localePrefix });