Further customization of register link

[thepaperpilot]

Describe the problem

I have a cinny instance where I'm disallowing custom home servers and the only home server option uses SSO. The login dialog shows a register link that is effectively non-functional, as the only allowed home server will throw an error when it is clicked.

Describe the solution you'd like

In this case I'd appreciate being able to make the register link go to a custom page where they can actually register (zitadel in my case). Hiding the text entirely would also work, although suboptimal.

Alternatives considered

No response

Additional context

This problem has been discussed in this FR however the response was that the original FR was implemented, so I'm making this one and I believe it is not a duplicate, or else that PR would have been re-opened.