Fixes Warrior Pulls continuously breaking after lunging a M56D/M2C us…

…er from front (#5151)

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So that one took a lot of debugging...

To keep it as short as possible, when you lunge a M56D/M2C user from
front as Warrior, they get stunned. The stun cancels their HMG
interaction, causing them to step away. This means they leave the grab
range, breaking it. Warrior code incorrectly re-sets pulledby, resulting
in a mob "pulledby" one that doesn't pull it.

In practice once this happens, this means that the "incorrectly" pulled
mob will reset any active grabs from the Warrior when it moves. Negating
the use of lunges completely.


# Changelog
:cl: Firartix, Birdtalon
fix: Fixed a logic error in Warrior code causing lunging some M2C/M56D
users to semi-permanently brick lunge.
/:cl:

---------

Co-authored-by: BeagleGaming1 <[email protected]>

code/modules/mob/living/carbon/xenomorph/castes/Warrior.dm

@@ -96,7 +96,8 @@
 		if(should_neckgrab && living_mob.mob_size < MOB_SIZE_BIG)
 			living_mob.drop_held_items()
 			living_mob.apply_effect(get_xeno_stun_duration(living_mob, 2), WEAKEN)
-			living_mob.pulledby = src
+			if(living_mob.pulledby != src)
+				return // Grab was broken, probably as Stun side effect (eg. target getting knocked away from a manned M56D)
 			visible_message(SPAN_XENOWARNING("[src] grabs [living_mob] by the throat!"), \
 			SPAN_XENOWARNING("You grab [living_mob] by the throat!"))
 			lunging = TRUE