Minecraft progression fix

* Change the rail crafting recipe to use copper instead of iron. * Significantly increase minecart speed. * Make Netherite items indestructible by default, removing their durability bar. * Prevent Netherite items from receiving Mending and Unbreaking enchantments. * Require enchanted books to be placed on bookshelves at the enchantment table to unlock specific enchantments. * Remove levels from enchanted books, allowing the player to select the enchantment level directly at the enchantment table; higher levels cost more experience and lapis lazuli. * Remove the "Too Expensive" limit on the anvil. * Remove the exponential increase in experience cost caused by repeated anvil use. * Include books with unique enchantments in structure loot based on difficulty level. * Improve Stronghold rewards to match the difficulty of the final challenge. * Allow the player to crouch while riding a horse to lower their hitbox and pass under blocks or leaves. * Make crouching on horseback slower than galloping, while remaining faster than walking on foot. * Allow horses to swim slowly while the player is mounted. * Increase base potion duration and allow mixing different potions in a cauldron to combine their effects into a single bottle. * Implement a system where repeatedly consuming the same food temporarily reduces the saturation gained. * Allow complex foods like stews and soups to stack up to 16 items. *