oficial/app/resources/routes/04_ventas.php

<?php
use Incoviba\Controller\Ventas;

$app->group('/ventas', function($app) {
    $files = new FilesystemIterator(implode(DIRECTORY_SEPARATOR, [__DIR__, 'ventas']));
    foreach ($files as $file) {
        if ($file->isDir()) {
            continue;
        }
        include_once $file->getRealPath();
    }
    $app->get('[/]', Ventas::class);
});