Riddonkulous

I wear a thousand tiny coats, yet never feel the cold, I hide a juicy treasure that is worth its weight in gold. I sit upon the kitchen shelf or tumble in a bowl, and one small bite of summer is my secret little goal. My outside shines like sunshine, my inside wears a crown, and when you slice me open, sweet juice might tumble down. I travel in a lunchbox, make a smoothie bright, and turn a simple summer day into pure delight. I have no feet to run away, no hands to wave hello, but give me warmth and water and watch my garden grow. Some say I'm nature's candy, some enjoy me chilled, and once my sweetness hits your tongue, your cravings may be filled. What am I, this golden treat, both juicy, sweet, and neat?