feat(i18n): add French language support and enhance localization

- Introduced French as a supported language across the application, updating locale files and adding translations for various components.
- Enhanced language handling logic to accommodate French, ensuring proper detection and fallback mechanisms.
- Updated UI elements to include French language options, improving accessibility for French-speaking users.
- Refactored SEO handling to include French in hreflang links, enhancing search engine indexing for multilingual content.
- Added new scripts for managing French translations and ensuring consistency across language files.

frontend/src/i18n/index.js

@@ -80,6 +80,26 @@ import esMessage from './locales/es/message.json';
 import esPersonal from './locales/es/personal.json';
 import esSeo from './locales/es/seo.json';
 
+import frGeneral from './locales/fr/general.json';
+import frHeader from './locales/fr/header.json';
+import frNavigation from './locales/fr/navigation.json';
+import frHome from './locales/fr/home.json';
+import frChat from './locales/fr/chat.json';
+import frRegister from './locales/fr/register.json';
+import frError from './locales/fr/error.json';
+import frActivate from './locales/fr/activate.json';
+import frSettings from './locales/fr/settings.json';
+import frAdmin from './locales/fr/admin.json';
+import frSocialNetwork from './locales/fr/socialnetwork.json';
+import frFriends from './locales/fr/friends.json';
+import frFalukant from './locales/fr/falukant.json';
+import frPasswordReset from './locales/fr/passwordReset.json';
+import frBlog from './locales/fr/blog.json';
+import frMinigames from './locales/fr/minigames.json';
+import frMessage from './locales/fr/message.json';
+import frPersonal from './locales/fr/personal.json';
+import frSeo from './locales/fr/seo.json';
+
 function isPlainObject(value) {
   return value !== null && typeof value === 'object' && !Array.isArray(value);
 }
@@ -212,14 +232,36 @@ const messages = {
     ...esMessage,
     ...esPersonal,
     ...esSeo,
-  }
+  },
+  fr: {
+    ...frGeneral,
+    ...frHeader,
+    ...frNavigation,
+    ...frHome,
+    ...frChat,
+    ...frRegister,
+    ...frPasswordReset,
+    ...frError,
+    ...frActivate,
+    ...frSettings,
+    ...frAdmin,
+    ...frSocialNetwork,
+    ...frFriends,
+    ...frFalukant,
+    ...frBlog,
+    ...frMinigames,
+    ...frMessage,
+    ...frPersonal,
+    ...frSeo,
+  },
 };
 
 const i18n = createI18n({
   locale: store.state.language,
   fallbackLocale: {
     ceb: ['en', 'de'],
-    default: ['de']
+    fr: ['de'],
+    default: ['de'],
   },
   messages
 });