Best methods for building Spell & Abilities "once per day"

Whats the best method(s) for setting abilities(even item abilities) to a "once per day" setting?

I dont want to require a stay at an inn, but want to allow for "long rests" or camping to restore.

Am I going to need to create a variable that tracks "time since used"?

When you have a rest event just use nodes to replenish your spell slots. Don't need to track time.

Abilities have Use Count options in their use cost settings. E.g. setting it up without any auto resets will make the reset completely up to you.

You can use the Change Ability Use Count node to reset all abilities of a combatant.