adding a bind shell that can allow for more practice with future
features such as multiple transports, encryption, transferring files,
and a more robust client interface
Made it use a single UDP client as well as proper randomized ports to go
through network firewalls, requiring stdin, status, stderr, and stdout
all go over a single UDP socket
Updated the client to have a prompt
replaced dev container Dockerfile with one which uses
Ubuntu instead of Alpine. The Docker in Docker feature only
works on Ubuntu, not Debian or Alpine, and the LLDB extension
to enable debugging only supports Debian/Ubuntu
