api(application): add endpoints for (de)attaching eggs and nodes on mounts

app/Http/Requests/Api/Application/Mounts/MountAddNodesRequest.php

@@ -0,0 +1,31 @@
+<?php
+
+namespace Pterodactyl\Http\Requests\Api\Application\Mounts;
+
+use Pterodactyl\Services\Acl\Api\AdminAcl;
+use Pterodactyl\Http\Requests\Api\Application\ApplicationApiRequest;
+
+class MountAddNodesRequest extends ApplicationApiRequest
+{
+    /**
+     * @var string
+     */
+    protected $resource = AdminAcl::RESOURCE_MOUNTS;
+
+    /**
+     * @var int
+     */
+    protected $permission = AdminAcl::WRITE;
+
+    /**
+     * ?
+     *
+     * @param array|null $rules
+     *
+     * @return array
+     */
+    public function rules(array $rules = null): array
+    {
+        return $rules ?? ['nodes' => 'required|exists:nodes,id'];
+    }
+}