GHSCI app nicegui link when clicked is invalid (ideally this would be customised)

[carlhiggs]

Describe the bug
When starting the GHSCI app (ghsci at prompt within GHSCI docker image), the welcome message from NiceGUI suggests to join from https://localhost:8080 (and an additional URL, that won't work, and which should be omitted). However, when clicked on in terminal, an error appears warning This link is invalid: https://localhost:8080,. That is purely because there is a comma incorrectly interpreted as being in the connection URL. In fact, the intended URL as it would otherwise be read by a user is fine.

This was tested using v4.5.3 of the GHSCI app.

The ideal solution is to define a custom welcome message. I think the reason we haven't already done this is that it didn't used to be possible. However, I believe it now may be, as per here.