Chiseled Bookshelf/BE


 * Block entity data
 * : List of books in the bookshelf.
 * : An item, including the slot tag. The valid slot numbers are 0-5.
 * : Last interacted slot (0–5), or -1 if no slot has been interacted with yet.
 * : Last interacted slot (0–5), or -1 if no slot has been interacted with yet.
 * : Last interacted slot (0–5), or -1 if no slot has been interacted with yet.