network, citra_qt: Give moderation permission to community mods

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.

src/network/room.h

@@ -74,6 +74,7 @@ enum RoomMessageTypes : u8 {
     IdModBanListResponse,
     IdModPermissionDenied,
     IdModNoSuchUser,
+    IdJoinSuccessAsMod,
 };
 
 /// Types of system status messages