Revert "Revert "Garbage collection, asset delivery, icon2html revolution, and…" (#15816)

This reverts commit f6d0f62622.

code/modules/organs/organ_external.dm

@@ -87,16 +87,21 @@
 
 	if(parent && parent.children)
 		parent.children -= src
+		parent = null
 
 	if(children)
 		for(var/obj/item/organ/external/C in children)
+			children -= C
+			C.parent = null
 			qdel(C)
 
 	if(internal_organs)
 		for(var/obj/item/organ/O in internal_organs)
+			internal_organs -= O
 			qdel(O)
 
 	if(splinted && splinted.loc == src)
+		splinted.loc = null
 		qdel(splinted)
 	splinted = null