Problem

Right now, when CLI connections to workspaces fail (ssh, port-forward, ping, speedtest, etc) we often don't surface any human readable diagnostics that could help customers self-troubleshoot.

Proposal

When we fail to connect, we could present a brief checklist of what requirements succeeded or failed:

1. Could we connect to Coder server?
2. Is the agent connected to Coder server?
3. Did we connect to DERP?
4. Did we Coordinate?
   1. Did we send our node?
   2. Did we get the Agent node?
5. Did Disco succeed?
6. Did Wireguard handshake?