Refactor chat module and navigation components for improved user experience

- Update app configuration to load chat module on startup for route registration.
- Introduce useModularNavigation composable for dynamic navigation based on enabled modules.
- Simplify Navbar.vue by utilizing userMenuItems for dropdown and button rendering, enhancing maintainability.
- Enhance ChatPage.vue with detailed debug information and user authentication checks for better feedback.

src/app.config.ts

@@ -42,7 +42,7 @@ export const appConfig: AppConfig = {
     chat: {
       name: 'chat',
       enabled: true,
-      lazy: true, // Load on demand
+      lazy: false, // Load on startup to register routes
       config: {
         maxMessages: 500,
         autoScroll: true,