More precise object targeting

Fixed

• Object highlighting now covers only the object you point at. Two deposit chests standing side by side no longer light up together, and the strips of wall next to trees and chests stay dark.
• Standing in a doorway now closes the door you are standing in, not the one beside it — the character menu offers the action of the object on your own tile.
• Large objects such as deposit chests and fireplaces now respond to the cursor across their whole graphic, not just its right half.