Better error for connect/shell on connection failure

EDIT I realized it was due to a connectivity issue with my VPN. Ideally the CLI would return a more helpful error in this situation. I've updated the title accordingly

I've encountered an issue where the connect and shell commands immediately error

❯ pscale connect load_testing main
Secure connection to database load_testing and branch main is established!.

Local address to connect your application: 127.0.0.1:3306 (press ctrl-c to quit)
Error: unimplemented: unary response has zero messages
❯ pscale shell load_testing main
ERROR 2003 (HY000): Can't connect to MySQL server on '127.0.0.1:54288' (61)
Error: unimplemented: unary response has zero messages

I can see the database so I don't think it's an auth issue

❯ pscale database show load_testing
  NAME           CREATED AT     UPDATED AT     NOTES  
 -------------- -------------- -------------- ------- 
  load_testing   23 hours ago   23 hours ago 

Version:

❯ pscale --version
pscale version 0.226.0 (build date: 2025-02-27T22:07:04Z commit: 87ec48f)

Begin with the pscale connect and pscale shell entry points and reproduce the VPN/connectivity failure using the commands and version in the report. Trace where unimplemented: unary response has zero messages is surfaced; done means these commands return a more helpful connectivity error for this situation.