Prompt/warn users before causing them to lose due to idling

The client causes users to be kicked due to idling without warning, even if they're still taking OS actions such as moving the mouse and hovering over cards while making decisions. In formats like EDH where board states are large and decisions can take a while, potentially without taking game actions but still being active. Warning the user that they will be kicked for being idle a few minutes in advance would help alleviate the issue, as would having mouse actions count as things that prevent the game from thinking the player is being idle.