QSS join message should be simpler

[holmesworcester]

Right now we're showing the explanation about joining with Tor, even when using QSS.

We should simplify the joining message in the QSS case:

https://www.figma.com/design/dSEZJr9crJjcV3ILogea9C/Join-from-invite-link---prototype?node-id=2894-3382&t=nbsLaSNDsxGNtOZU-4