Moves all stack object sprites from items_and_weapons.dmi to their own file

code/game/objects/items/stacks/medical.dm

@@ -1,7 +1,7 @@
 /obj/item/stack/medical
 	name = "medical pack"
 	singular_name = "medical pack"
-	icon = 'icons/obj/items_and_weapons.dmi'
+	icon = 'icons/obj/stack_objects.dmi'
 	amount = 6
 	max_amount = 6
 	w_class = WEIGHT_CLASS_TINY

code/game/objects/items/stacks/sheets/mineral.dm

@@ -63,7 +63,7 @@ GLOBAL_LIST_INIT(sandstone_recipes, list ( \
 
 /obj/item/stack/sheet/mineral/sandbags
 	name = "sandbags"
-	icon = 'icons/obj/items_and_weapons.dmi'
+	icon = 'icons/obj/stack_objects.dmi'
 	icon_state = "sandbags"
 	singular_name = "sandbag"
 	layer = LOW_ITEM_LAYER

code/game/objects/items/stacks/stack.dm

@@ -8,6 +8,7 @@
  * Stacks
  */
 /obj/item/stack
+	icon = 'icons/obj/stack_objects.dmi'
 	origin_tech = "materials=1"
 	gender = PLURAL
 	var/list/datum/stack_recipe/recipes