I want to forward an ongoing call to another UA. I believe this is currently not possible;
going off examples/accept_invite.rs, I think it would require either access to the dialog
from the call, so that something like dialog.create_request could be done from there,
or something like call.refer() could be added?

I have a scenario like this: 2 softphones and one ezk-based application X connected to a softswitch.
Softphone A is calling X and X at some point transfer the call to Softphone B, based on the incoming audio.