Arena draw farming countermeasure

[Fulmene]

We should have some system set up to prevent "draw farming", especially near the end of the arena. Lichess has the draw streak rule.

From Lichess's arena tournament FAQ

Draw streaks: When a player has consecutive draws in an arena, only the first draw will result in a point, or draws lasting more than 30 moves. The draw streak can only be broken by a win, not a loss or a draw.

Our rule might differ, but what exactly to implement is up for discussion.