Use autoload for loading legacy craft so it only loads when needed (#18093)

Author: riasvdv

src/Cms.php

@@ -22,7 +22,7 @@
 
     public static function config(): GeneralConfig
     {
-        return app(GeneralConfig::class);
+        return app(GeneralConfig::class) ?? GeneralConfig::create();
     }
 
     public static function systemName(): string

yii2-adapter/src/Yii2ServiceProvider.php

@@ -353,9 +353,13 @@ public function boot(): void
         ));
 
         /**
-         * Load Craft
+         * Load Craft when necessary
          */
-        app('Craft');
+        spl_autoload_register(function($class) {
+            if ($class === 'Craft') {
+                app('Craft');
+            }
+        });
 
         $this->ensureNewMigrationTable();