The situation where both players are locked in and not attacking is similar to the situation with the snake and the dwarves. In one case, the player cannot attack due to the dwarves' low speed, and in the other, he is prevented by the unwillingness to expose himself to attack. In short, it's the attacker's problem; if he wants to attack, let him; if he doesn't, let him retreat. The defender stood there and didn't touch anyone.
And there's no need to create more buttons.
At most, what needs to be done is to give a general definition of a stalemate situation in the rules. For example: a stalemate situation is considered to be a situation where, for 5 (the number needs to be discussed) consecutive rounds, neither side receives any damage.
However, it will not be possible to determine a stalemate only by the absence of damage. For example, one stands in defense, buffed with useful spells, and the other simply waits for these buffs to expire. With a strength of 40 and a collection of spells that increase spell duration, he will have to wait 90 rounds, but this is not a stalemate.