Customizable Invitation Links for Matrix

[DonPrus]

I'm proposing a new feature for Matrix that would allow users to customize the domain used in invitation links, moving beyond the default matrix.to.

This would enable users to replace matrix.to with any domain of their choice, offering more flexibility and personalization. By implementing this feature, users could align the invitation links with their own domains or preferred URL formats, enhancing both the appearance and the coherence of their communications.

This change could greatly improve branding consistency and user trust, especially for organizations using Matrix for their internal communications.