Dice bust scorer

Score one round of a two-dice game called Push Your Luck.

A player has a running total. In a round they roll two dice again and again; rolls lists the rolls they will make in order, each as [a, b]. A round has a score that starts at 0, and each roll is handled as follows:

• If exactly one die shows a 1, it is a bust: the round's score is lost, the round ends, and total is unchanged.
• If both dice show 1 (snake eyes), the round ends and the player loses everything: total becomes 0.
• Otherwise the roll is worth a + b points, and doubled if a == b (so [3, 3] is worth 12). Add it to the round's score. If the round's score is now 30 or more, the player banks it automatically: the score is added to total and the round ends.

When a round ends, any remaining rolls are never made, so they do not matter. If rolls runs out before anything ends the round, the player stops and banks the current score.

Input: total, the player's total before the round, and rolls, a list of [a, b] pairs.

Output: a list [newTotal, rollsUsed], where rollsUsed is the number of rolls that were actually made (including the roll that ended the round).