Add documentation for Filament Phone Input setup

Updated the README to include steps for publishing Filament Phone Input assets and integrating the WhatsappWidget plugin in the AdminPanelProvider. This ensures clearer guidance for setting up these components.

Author: jeffersongoncalves

README.md

@@ -33,6 +33,17 @@ Publish assets file.
 
 ```bash
 php artisan vendor:publish --tag=whatsapp-widget-assets
+php artisan vendor:publish --tag=filament-phone-input-assets
+```
+
+Add in AdminPanelProvider.php
+
+```php
+use JeffersonGoncalves\Filament\WhatsappWidget\WhatsappWidgetPlugin;
+
+->plugins([
+    WhatsappWidgetPlugin::make(),
+])
 ```
 
 Add head template.