Does each side of a double sink require a separate trap, to prevent a backup from meat to dairy or vice versa, or can both sides lead to 1 trap?

ב"ה Shalom, I see no reason for a separate drain trap for meat and dairy. On the rare occasion of blockage of the drain, anything coming up will not be at a boiling temperature, and even if would be, it would be mixed with soap and other foul-tasting waste which would not make anything not kosher. In addition, regular household maintenance usually prevents clogging. All the best