Add very simple download files doc

Author: romain

doc/index.rst

@@ -1326,6 +1326,51 @@ The files will be available in a regular ``$request->files`` files bag::
     need to specify ``multiple`` attribute on HTML element and end ``name``
     with ``[]``.
 
+.. _downloads:
+
+Downloading files
+-----------------------
+
+Currently, Live Components do not natively support returning file responses directly from a LiveAction. However, you can implement file downloads by redirecting to a route that handles the file response.
+
+Create a LiveAction that generates the URL for the file download and returns a `RedirectResponse`::
+
+       use Symfony\Component\HttpFoundation\RedirectResponse;
+       use Symfony\Component\Routing\Generator\UrlGeneratorInterface;
+       use Symfony\UX\LiveComponent\Attribute\LiveAction;
+
+       // ...
+
+       class MyDownloadButton
+       {
+           // ...
+
+           #[LiveAction]
+           public function initiateDownload(UrlGeneratorInterface $urlGenerator): RedirectResponse
+           {
+               $url = $urlGenerator->generate('app_file_download');
+               return new RedirectResponse($url);
+           }
+       }
+
+.. code-block:: html+twig
+
+   <div {{ attributes }} data-turbo="false">
+       <button
+           data-action="live#action"
+           data-live-action-param="initiateDownload"
+       >
+           Download
+       </button>
+   </div>
+
+When Turbo is enabled, it will intercept the redirect and initiate a second request for the download URL. Adding `data-turbo="false"` ensures that the download URL is called only once.
+
+.. note::
+
+   Native support for file downloads in Live Components is under development. For more details, refer to the related `pull request #2483 <https://github.com/symfony/ux/pull/2483>`_.
+
+
 .. _forms:
 
 Forms