Enforce distribution of dissection in SCORU refutation game
The implementation of the SCORU refutation game currently enforces some constraints on dissections played during the game---they must be 32 states long, or the maximum possible if that is less than 32. However, there is no constraint on the distribution of these states through the tick-time of the computation. This allows an availability attack where two dishonest stakers play a refutation game between themselves and can extend that game over a number of blocks linear in the tick-duration on the commitment.
We would like the maximum length of a game to be logarithmic in the tick-duration. This can be achieved with a modest further restriction to dissections: the refutation game rules should enforce that the maximum tick-duration between two sequential states in the dissection should be less than a constant factor 1/f
of the total tick-duration of the previous dissection. Initially f
can be hard-coded as 2.