Update options.md with Symfony 6.4 installation steps

Added instructions for installing Symfony 6.4 and configuring FrankenPHP.

Author: abdounikarim

docs/options.md

@@ -25,6 +25,27 @@ On Windows:
 set SYMFONY_VERSION=6.4.* && docker compose up --wait&set SYMFONY_VERSION=
 ```
 
+> [!NOTE]
+>
+> If you install a Symfony 6.4 version, you also need to do these steps:
+> ```bash
+> composer require runtime/frankenphp-symfony
+> ```
+>
+> Add this content `env APP_RUNTIME Runtime\FrankenPhpSymfony\Runtime` in the `frankenphp/Caddyfile` on the `worker`section.
+
+```Caddyfile
+frankenphp {
+        {$FRANKENPHP_CONFIG}
+
+        worker {
+                file ./public/index.php
+                env APP_RUNTIME Runtime\FrankenPhpSymfony\Runtime
+                {$FRANKENPHP_WORKER_CONFIG}
+        }
+}
+```
+
 ## Installing Development Versions of Symfony
 
 To install a non-stable version of Symfony,