update,

laravel-simple-tryout/php74-httpd/example-app/app/Providers/BroadcastServiceProvider.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace App\Providers;
+
+use Illuminate\Support\Facades\Broadcast;
+use Illuminate\Support\ServiceProvider;
+
+class BroadcastServiceProvider extends ServiceProvider
+{
+    /**
+     * Bootstrap any application services.
+     */
+    public function boot(): void
+    {
+        Broadcast::routes();
+
+        require base_path('routes/channels.php');
+    }
+}