This code configuration forces EM initialisation on bootstrap on each request - even if DB is not used.

/**
 * SyliusCoreBundle::boot() reads 'sylius_core.order_by_identifier' on every request and, if true,
 * eagerly does $container->get('doctrine.orm.entity_manager')->getConfiguration()->setDefaultQueryHint(...),
 * forcing the (otherwise lazy) default entity manager to build even on requests that never touch the DB.
 *
 * We bake the same hint into the entity manager's own Configuration definition at compile time instead
 * (it becomes part of the EM's normal one-time construction, no separate eager fetch), then flip the
 * parameter to false so Sylius's boot() skips its own runtime call. Net effect on ordering is unchanged.
 */
final class BakeOrderByIdentifierQueryHintPass implements CompilerPassInterface
{
    private const PARAMETER = 'sylius_core.order_by_identifier';
    private const CONFIGURATION_ID = 'doctrine.orm.default_configuration';

    public function process(ContainerBuilder $container): void
    {
        if (!$container->hasParameter(self::PARAMETER)) {
            return;
        }

        $wasEnabled = (bool) $container->getParameter(self::PARAMETER);

        if ($wasEnabled && $container->hasDefinition(self::CONFIGURATION_ID)) {
            $container->getDefinition(self::CONFIGURATION_ID)->addMethodCall('setDefaultQueryHint', [
                Query::HINT_CUSTOM_TREE_WALKERS,
                [OrderByIdentifierSqlWalker::class],
            ]);
        }

        $container->setParameter(self::PARAMETER, false);
    }
}