Failed shuffle behavior

[emergent-reasons]

The server should be tracking as little state as possible, but there are still many points where the server knows a shuffle is no longer possible. What should it do?

• e.g. a ban is applied
• e.g. it detects that a player in an active/frozen pool has disconnected
• Currently the server does not disconnect players and does not send a message about detected failure.
• I recommend the server broadcast a failed shuffle message and then do nothing - let the clients decide what to do such as send blames, disconnect or whatever. This risks a malicious player sitting in a dead pool and pinging the server with messages to keep it alive but... it's a dumb an inefficient attack so deal with it later if that becomes an issue.