Some thoughts

Renderer.php

<?php
namespace Aura\Web_Kernel;

class Renderer
{
    public $data;
    
    public $renderer;
    
    public $view;
    
    public $layout;
    
    public $response
    
    public function setRenderer($renderer)
    {
        $this->renderer = $renderer;
    }
    
    public function setResponse(Aura\Web\Response $response)
    {
        $this->response = $response;
    }
    
    public function __invoke()
    {
        // as in framework
        if ($this->response->getContent() == null) {
            $content = $this->renderer->render($this->data, $this->view, $this->layout);
        }        
    }
}