On Room non-existing joined

[wowawiwa]

Currently: It displays Loading.
Expected: Proceed as if the roomID hasn'nt been given.

Currently, there is no way for the FE to distinguish if the join-room request is taking time or if the room doesn't exist.
At best the BE would return an error status code on a request to join a non-existing room. Or it could send an event later.

[abustany]

Yeah we clearly need a pattern here to deal with commands that can fail... Currently a command being "successful" just means it's been successfully received by the server, but not that it was successfully processed by the retro "object". The retro will currently just ignore invalid commands, but we need to be better at surfacing those errors. But then do we need to identify which command caused an error? If so do we need (optional) command IDs akin to the id field in JSON-RPC calls?

[wowawiwa]

Wouldn't it be okay to send room-not-found with the payload of the room when the client tries to connect to a non existing room?