It doesn't, but I've wished it did. Probably as a toggled option, since I know it would aggravate others.

It would require a couple more Act 2 safe zones scattered about for the player to keep track of, but it makes more sense than the ability to just chill for a while in what can be some incredibly unsafe territory. Sneaking off to bang in the underdark? Sure. Fine. I'm certain that won't cause any undue noise.

There are only 1-2 battles I'm aware of that can or absolutely will happen, and neither are randomized encounters in the same vein. Areas it notes are dangerous, it won't allow you to rest at all.