[REFACTOR] Helper proc for unbuckling a mob (#26918)

* Helper proc from unbuckling a mob

* Rename to unbuckle

* Minor fixes

* Move buckled up /mob/living

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Co-authored-by: Adrer <adrermail@gmail.com>

code/game/objects/items/tools/wirecutters.dm

@@ -36,7 +36,7 @@
 		user.visible_message("<span class='notice'>[user] cuts [C]'s restraints with [src]!</span>")
 		QDEL_NULL(C.handcuffed)
 		if(C.buckled && C.buckled.buckle_requires_restraints)
-			C.buckled.unbuckle_mob(C)
+			C.unbuckle()
 		C.update_handcuffed()
 		return
 	else