[Webhook] [Notifier] Added documentation for Webhook in combination with the Notifier component

Author: TimoBakx

webhook.rst

@@ -130,3 +130,48 @@ final readonly class WebhookListener implements ConsumerInterface
         // Handle the mail engagement event
     }
 }
+
+Usage in combination with the Notifier component
+------------------------------------------------
+
+The usage of the Webhook component when using a third-party transport in
+the Notifier is very similar to the usage with the Mailer.
+
+Currently, the following third-party sms transports support webhooks:
+
+============ ==========================================
+SMS service  Parser service name
+============ ==========================================
+Twilio       ``notifier.webhook.request_parser.twilio``
+============ ==========================================
+
+.. versionadded:: 6.3
+
+    Webhook support for the Twilio service was introduced in Symfony 6.3.
+
+For SMS transports, an additional ``SmsEvent`` is available in the RemoteEvent
+consumer::
+
+use Symfony\Component\RemoteEvent\Attribute\AsRemoteEventConsumer;
+use Symfony\Component\RemoteEvent\Consumer\ConsumerInterface;
+use Symfony\Component\RemoteEvent\Event\Sms\SmsEvent;
+use Symfony\Component\RemoteEvent\RemoteEvent;
+
+#[AsRemoteEventConsumer('notifier_twilio')]
+final readonly class WebhookListener implements ConsumerInterface
+{
+    public function consume(RemoteEvent $event): void
+    {
+        if ($event instanceof SmsEvent) {
+            $this->handleSmsEvent($event);
+        } else {
+            // This is not an sms event
+            return;
+        }
+    }
+
+    private function handleSmsEvent(SmsEvent $event): void
+    {
+        // Handle the sms event
+    }
+}