Upgradable Bookshelves

This mod introduces two new types of bookshelves into the game that significantly outperform the standard version in efficiency.

Golden Bookshelf has double the performance compared to a regular bookshelf. To craft it, you need to place 4 gold ingots around a standard bookshelf in the crafting recipe.

Emerald Bookshelf is even more powerful - its efficiency is three times higher than the base version. The recipe for its creation is similar to the golden shelf, but emeralds are used instead of gold ingots.