Add member label to user dropdown that opens when starting to mention someone

[SimoneZaza]

Description

As a user, I want to see whether the person I intend to mention is member of this Space (or even admin or lead)

Acceptance criteria

• [ ] Add the word "member" "admin" or "lead" behind the user name in the mention dropdown
• [ ] align to the right, color: neutral light (or same as text color of the name), font: caption small
• [ ] Needs adding a query

Additional Context

Areas that will be affected

To be added during the refinement