Negotiating connection upgrade

[Rekseto]

Node A - node with public IP
Node B - mobile device (without moderate NAT)

Node A connects to Node B on startup through ToR (unusual to happen as most of the time Node B will connect to Node A through TCP due to low latency but still a possibility), when we will start transferring something through Tor link (e.g file) StreamPressureEvent will occur, Node A has no possibility of upgrading connection to Node B (due to no moderate NAT present), but Node B would have that possibility by connecting to node A through TCP.

Upgrading connection could be of higher layer (migrating sessions stays at stream initiator side)