feat(settings/options/language): implement language selection menu

nuxt.config.ts

@@ -20,7 +20,14 @@ export default defineNuxtConfig({
   },
   i18n: {
     strategy: "no_prefix",
-    locales: [{ code: "en", language: "en-US", file: "en.json" }],
+    locales: [
+      { code: "en", language: "en-US", name: "English", file: "en.json" },
+      { code: "de", language: "de-DE", name: "Deutsch", file: "de.json" },
+      { code: "fr", language: "fr-FR", name: "Français", file: "fr.json" },
+      { code: "es", language: "es-ES", name: "Español", file: "es.json" },
+      { code: "it", language: "it-IT", name: "Italiano", file: "it.json" },
+      { code: "ja", language: "ja-JP", name: "日本語", file: "ja.json" },
+    ],
     defaultLocale: "en",
   },
   image: {