Allow to copy sale-price from other item

Add an option in the public tabs of the chest to set the price of an item by referencing another (the option to copy the price by hovering over another item, a similar game mechanic is in the window for choosing preferred Atlas maps).

This will significantly speed up the listing of items for sale, especially almost identical ones, such as Beasts or Blueprints.

+1
definitely would be a very nice qol