Make disembodied limbs face south, standardize dir to defines (#30688)

code/modules/surgery/organs/organ_external.dm

@@ -66,6 +66,10 @@
 	///The level of false skin used to cover robotic organs on the limb. Updated when too damaged, when installed, or when an organ with it is installed.
 	var/augmented_skin_cover_level = 0
 
+// When the limb is not on a person, make sure it faces south so it's always visible.
+/obj/item/organ/external/setDir()
+	dir = SOUTH
+
 /obj/item/organ/external/necrotize(update_sprite=TRUE, ignore_vital_death = FALSE)
 	if(status & (ORGAN_ROBOT|ORGAN_DEAD))
 		return
@@ -645,7 +649,7 @@ Note that amputating the affected organ does in fact remove the infection from t
 			parent.receive_damage(total_brute, total_burn, ignore_resists = TRUE) //Transfer the full damage to the parent, bypass limb damage reduction.
 		parent = null
 
-		dir = 2
+		dir = SOUTH
 
 	if(victim)
 		victim.updatehealth("droplimb")
@@ -663,7 +667,7 @@ Note that amputating the affected organ does in fact remove the infection from t
 				// Throw limb around.
 				if(src && isturf(loc))
 					dropped_part.throw_at(get_edge_target_turf(src,pick(GLOB.alldirs)),rand(1,3),30)
-				dir = 2
+				dir = SOUTH
 			brute_dam = 0
 			burn_dam = 0  //Reset the damage on the limb; the damage should have transferred to the parent; we don't want extra damage being re-applied when then limb is re-attached
 			return dropped_part