XS Web Server - can I make file "crossdomain.xml" available in the root of the XS server?

I want to make an XML file available in the root of my XS server.  Specifically, I'd like to make a file called "crossdomain.xml" available here:

http://<myhanaserver>:8000/crossdomain.xml

I cannot do this by creating the file in HANA Studio and uploading it to the server in the usual way, because an XS project has to have a repository package.  If it has a repository package then that means it is no longer in the root of the domain.

Background

I want to connect up a product called Unity to my HANA system, and the Unity documentation says this is the approach I need to follow.  I know I can look into other options like anonymous logins and CORS, but I'd like to try out the "Unity way" first.

Thanks, Kevin.