feat(i18n): Add localized language names to internationalization schema

- Extend `LocaleMessages` type with `locales` field for language names
- Update English, Spanish, and French locales with native language names
- Enhance internationalization type safety and locale representation

src/i18n/types.ts

@@ -19,6 +19,14 @@ export interface LocaleMessages {
     serverError: string
     networkError: string
   }
+  // Language names in the current language
+  locales: {
+    en: string
+    es: string
+    fr: string
+    de: string
+    zh: string
+  }
   // Add date/time formats
   dateTimeFormats: {
     short: {