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.
Local apples are plentiful at farmer's markets, in the grocery store and if you're lucky, on the trees on your property. We feed our horses the apples from our trees when we can and store-bought apples other times of the year, and when we have extras, I like to treat the chickens with fun apple treats.