Here are the balance patch notes from Baldur’s Gate 3 Patch #1.
To my knowledge nothing has a global timer. And only a few quests have an actual time limit.
The only one I can think of is one where a character will die from poison gas if you take too long and go to camp too much - not even a long rest; just going to camp (as I learned the hard way when I went to camp to pick up stuff to sell from my trunk) and I came back to an empty zone and the dude’s corpse, and that route closes off a bunch of other quests. I had to reload right before I went to camp.