Porting putnams ventcrawling PR and Fix (#13571)

* Porting putnams rage

* And the bugfix

code/modules/mob/inventory.dm

@@ -100,6 +100,14 @@
 	return held_items.Find(I)
 
 
+///Find number of held items, multihand compatible
+/mob/proc/get_num_held_items()
+	. = 0
+	for(var/i in 1 to held_items.len)
+		if(held_items[i])
+			.++
+
+
 //Sad that this will cause some overhead, but the alias seems necessary
 //*I* may be happy with a million and one references to "indexes" but others won't be
 /mob/proc/is_holding(obj/item/I)

code/modules/mob/living/ventcrawling.dm

@@ -59,15 +59,8 @@ GLOBAL_LIST_INIT(ventcrawl_machinery, typecacheof(list(
 			if(!client)
 				return
 
-			if(iscarbon(src) && ventcrawler < 2)//It must have atleast been 1 to get this far
-				var/failed = 0
-				var/list/items_list = get_equipped_items(include_pockets = TRUE)
-				if(items_list.len)
-					failed = 1
-				for(var/obj/item/I in held_items)
-					failed = 1
-					break
-				if(failed)
+			if(iscarbon(src) && ventcrawler == VENTCRAWLER_NUDE)
+				if(length(get_equipped_items(include_pockets = TRUE)) || get_num_held_items())
 					to_chat(src, "<span class='warning'>You can't crawl around in the ventilation ducts with items!</span>")
 					return