Dont crash TUI if you can't connect to the socket

Hannes Siebenhandl
2024-03-08T08:29:27Z

```sh
$ cabal run ghc-debug-brick
Resolving dependencies...

ghc-debug-brick: Network.Socket.connect: <socket: 11>: does not exist (Connection refused)
```

I forgot to launch the application, the socket was still in the TUI, selecting it makes the app crash.
Seems a little bit excessive.