As PrettyFaces is a framework for JSF, action methods are executed from within the JSF lifecycle. In your configuration, PrettyFaces will try to execute the action method after the RESTORE_VIEW phase, which won’t ever happen, because in your case there is no JSF lifecycle.
I recommend to have a look at Rewrite, which is the successor of PrettyFaces. Rewrite just requires a Servlet environment and should therefore work fine for your use case. You could implement your usecase with something like this: