Moves sinks' layer to above the object layer (#68964)

This PR moves sinks to layer 3.2 as opposed to 3, the object layer.

Sinks are coded in with a pixel displacement and kitchen sinks are large enough for the collision check to fail if the sink is against a solid structure on an above layer, such as a window or an airlock.


Another big issue is that it looks bad

This is at the cost of 3 pixels appearing on top of a window if placed facing south against one, so this isn't a complete fix to the aesthetic of it, the primary focus of the PR is to make the sink interactable, and even then I believe it's a better trade-off:

code/game/objects/structures/watercloset.dm

@@ -256,6 +256,7 @@ MAPPING_DIRECTIONAL_HELPERS(/obj/structure/urinal, 32)
 	icon_state = "sink"
 	desc = "A sink used for washing one's hands and face. Passively reclaims water over time."
 	anchored = TRUE
+	layer = ABOVE_OBJ_LAYER
 	pixel_z = 1
 	///Something's being washed at the moment
 	var/busy = FALSE