Implement site structure synchronization between WordPress and IGNY8 backend

- Added a new API endpoint in the `IntegrationViewSet` to update the WordPress site structure, including post types and taxonomies.
- Implemented a function to retrieve the site structure and sync it to the IGNY8 backend after establishing a connection.
- Scheduled a daily cron job to keep the site structure updated.
- Enhanced the WordPress plugin to trigger synchronization upon successful API connection.
- Updated relevant files to support the new synchronization feature, improving integration capabilities.

igny8-wp-plugin/admin/class-admin.php

@@ -288,6 +288,9 @@ class Igny8Admin {
             __('Successfully connected to IGNY8 API and stored API key.', 'igny8-bridge'),
             'updated'
         );
+
+        // Sync site structure to backend (post types, taxonomies, etc.)
+        igny8_sync_site_structure_to_backend();
     }
 
     /**