アイヌ語追加 (#428) (#433)

Reviewed-on: #433
Co-authored-by: miteruzo <miteruzo@naver.com>

frontend/src/lib/messages.ts

@@ -0,0 +1,19 @@
+import { translateUIMessage } from '@/lib/i18n'
+
+import type navigation from '@/locales/ja/navigation.json'
+import type { LocaleCode } from '@/lib/locales'
+
+export type UIMessageKey = keyof typeof navigation
+
+
+export const uiMessage = (
+    locale: LocaleCode,
+    key: UIMessageKey,
+    values: Record<string, string | number> = { },
+): string => translateUIMessage (key, 'navigation', locale, values).text
+
+
+export const uiMessageLanguage = (locale: LocaleCode, key: UIMessageKey): 'ja' | 'ain' =>
+    translateUIMessage (key, 'navigation', locale).language === 'ain-Kana'
+    ? 'ain'
+    : 'ja'