Paint's GUI Peeper

Changes since v3:

* Changed all armor_stand entities to instead be the new item_display & text_display entities, cutting down on the number of entities required, how complicated they were to orient, and the lag produced by the datapack.

* Brewing stands now show their potion on the brewing stand itself as opposed to showing them floating above the brewing stand.

* The disc item that shows what disc is inside a jukebox will now orient itself to face you as opposed to having a fixed orientation along the north/south axis.

* All peepable blocks have always required "free space" above them, but since v3:

    * Trapdoors and signs (not hanging signs) are now considered "free space".

    * Brewing stands can now have hoppers above them and it won't kill the item_displays.

* pack_format is now 15, so the datapack expects to be ran in 1.20 or 1.20.1. (as of writing there is no 1.20.2 but it will most likely work there too).