Jot down TODOs.

client/src/handlers/room_join_response_handler.rs

@@ -28,7 +28,9 @@ impl MessageHandler for RoomJoinResponseHandler {
         )
         .context("joining room")?;
 
+      // TODO: Re-evaluate this with deadlocks in mind.
       // Send under lock to avoid out-of-order sends.
+      // TODO: Send details about the room too in the same response.
       let control_response =
         control::Response::RoomJoinResponse(control::RoomJoinResponse {
           room_name: response.room_name.clone(),