Establish Wi-Fi hotspot and connect to another device

Let's say that Alice wants to send a file to Bob. The idea is that if hole punching doesn't work well, then Alice can setup a Wi-Fi hotspot, and Bob would connect to it. After that, Alice and Bob are in the same local network and we don't need hole punching any more.

No files, tests, or entry points are identified in the issue. Begin by locating the existing hole-punching flow and determine how hotspot creation and device connection fit around it; done would mean Alice and Bob share a local network and file transfer no longer needs hole punching.

Written by the indexing model from the issue text.