Additional types which need Destroy to return qdel hints (and other Destroy fixes)

code/game/objects/items/antag_spawners.dm

@@ -12,7 +12,7 @@
 	sparks.attach(loc)
 
 /obj/item/weapon/antag_spawner/Destroy()
-	qdel(sparks)
+	qdel_null(sparks)
 	return ..()
 
 /obj/item/weapon/antag_spawner/proc/spawn_antag(client/C, turf/T)

code/game/objects/items/weapons/implants/implant.dm

@@ -52,6 +52,7 @@
 /obj/item/weapon/implant/Destroy()
 	if(part)
 		part.implants.Remove(src)
+	part = null
 	return ..()
 
 /obj/item/weapon/implant/attackby(obj/item/I, mob/user)