Based on the `roles` payload in the JWT, the rooms will now give mod permission to Citra Community Moderators. To notify the client of its permissions, a new response, IdJoinSuccessAsMod is added, and there's now a new RoomMember::State called Moderator.
Added verify_backend to load user_data for members. and removed method to generate UID as this is now done server-side.
Added GetUsername function and a "token" param to room_member.
Also added a username to ChatEntry, so that the username can be shown (along with nicknames) in the chat dialog.