The definition and abbreviation for Potentially Hazardous Food (Time/Temperature Control for Safety Food) or PHF/TCS should be modified to drop the reference to potentially hazardous food and PHF.
Yes, as a treat apples are fine for chickens. Some will say it is best not to feed them too many apples as the seed of an apple has a small amount of arsenic in it.
Typically, backyard and small farm chickens also eat food scraps from the farm household-basically anything besides beans, garlic, raw potatoes, onions, and citrus. You can feed them beans, garlic and onions but the eggs might taste funky.