Giving Echo Shards more uses: eternally baby mobs, reset villagers, potions

Echo shards are an intriguing item, and I've always disliked that they only have a single use. I think Mojang should lean into their time-altering aspects with a couple of new recipes.

1. Echo Apples. These would be crafted with an apple surrounded by 8 echo shards. These would be a slightly better food source than regular apples, and would also give you a bit of the new Longevity effect, described below. The main use of these would be to use on mobs - feeding one to a baby mob that would normally grow up will keep it a baby forever, a feature many people have been looking for. The effect could be reversed with a golden apple. Echo Apples could also be used on adult villagers to completely reset their trades, allowing you to try again for the item you're looking for, or change the profession entirely. This would discourage killing villagers with unwanted trades.

2. New effects: Longevity and Brevity. Echo shards could be used to brew potions of Longevity, which could be fermented for potions of Brevity. For as long as you have the Longevity effect, any effect you get (besides Longevity and Brevity) would last 30% longer. The Brevity effect would do the opposite, decreasing the length of any given effect. Longevity could be used when you want multiple positive effects and don't expect to be inflicted with many negative ones (e.g. Swiftness + Night Vision in Ancient Cities) while Brevity could be used when you expect to be hit with multiple negative effects (like in Trial Chambers).