There is no built-in functionality for this (though you could enable the option for taking a snapshot when logging off the computer).  Another possibility would be to have a simple .bat file Software Delivery task that runs AeXCMD.exe, waits for the snapshot to finish, then runs shutdown.exe -s to shutdown afterwards (or set the SWD program itself to shutdown the system after running).  If you are using Task server, I believe there are built-in tasks for taking a snapshot and Power control (including shut down), so you could build a job with those.

But, to the best of my knowledge there is no way to force a shutdown after the scheduled snapshot occurs.