Make session available in middleware

To make the session context available in a middleware, you have to push the middleware to the Router instead of the Kernel and add it to the web group.

public function boot(): void
{
    /** @var \Illuminate\Routing\Router $router */
    $router = $this->app->make(\Illuminate\Routing\Router::class);
    $router->pushMiddlewareToGroup('web', YourMiddleware::class);
}