Sundry Runtime Fixes - March (#5047)

* Fixes Runtime in tools.dm,239: undefined variable /mob/living/simple_animal/retaliate/solargrub/var/handcuffed

* Add logging to help identify the cause of runtime in examining zshadow mobs.

* Fix Runtime in buckling.dm,165: Cannot execute null.forceMove().

* Fixes  Runtime in robot_items.dm,31: Cannot read null.origin_tech

* Fixes Runtime in paper_bundle.dm,183: Cannot read null.loc

code/modules/multiz/zshadow.dm

@@ -33,6 +33,10 @@
 	. = ..()
 
 /mob/zshadow/examine(mob/user, distance, infix, suffix)
+	if(!owner)
+	 	// The only time we should have a null owner is if we are in nullspace. Help figure out why we were examined.
+		crash_with("[src] ([type]) @ [log_info_line()] was examined by [user] @ [global.log_info_line(user)]")
+		return
 	return owner.examine(user, distance, infix, suffix)
 
 // Relay some stuff they hear