Migrate stamps to the new attack chain. (#32002)

* Migrate stamps to the new attack chain.

* Migrate stamper module too.

code/modules/mod/modules/modules_maint.dm

@@ -125,7 +125,7 @@
 	desc = "A high-power stamp, able to switch between accept and deny mode when used."
 	flags = NODROP
 
-/obj/item/stamp/mod/attack_self__legacy__attackchain(mob/user, modifiers)
+/obj/item/stamp/mod/activate_self(mob/user)
 	. = ..()
 	if(icon_state == "stamp-ok")
 		icon_state = "stamp-deny"

code/modules/paperwork/stamps.dm

@@ -11,6 +11,7 @@
 	attack_verb = list("stamped")
 	/// What color will this crayon dye clothes, cables, etc? used for for updateIcon purposes on other objs
 	var/dye_color = DYE_GREEN
+	new_attack_chain = TRUE
 
 /obj/item/stamp/suicide_act(mob/user)
 	user.visible_message(SPAN_SUICIDE("[user] stamps 'VOID' on [user.p_their()] forehead, then promptly falls over, dead."))