Handle disconnects on player select + map select

[MaxCWhitehead]

Description

Right now if a client disconnects on player select, there is no indication / they do not leave on other clients.

In map select if player leaves and host selects map, game will not load / hang on black screen. If host leaves, players are stuck on map select.

To Reproduce

Start online game with two or more clients, and close one game during either player select or map select.

Expected Behavior

We should notify players / allow them to back out and matchmake again,or if at least 2 players remaining, allow to continue after removing that player.

Additional Context

No response

Log Messages

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