Makes pAI screen alert actually work (#68118)

Currently, when a pAI personality is submitted, it's supposed to show an alert screen briefly with flick. This doesn't work. So I've changed it to a 5 second overlay instead, and this does work.

code/game/objects/items/devices/paicard.dm

@@ -187,10 +187,19 @@
 	if(!COOLDOWN_FINISHED(src, alert_cooldown))
 		return
 	COOLDOWN_START(src, alert_cooldown, 5 SECONDS)
-	flick("[initial(icon_state)]-alert", src)
+	add_alert()
+	addtimer(CALLBACK(src, .proc/remove_alert), 5 SECONDS)
 	playsound(src, 'sound/machines/ping.ogg', 30, TRUE)
 	loc.visible_message(span_info("[src] flashes a message across its screen, \"Additional personalities available for download.\""), blind_message = span_notice("[src] vibrates with an alert."))
 
+/obj/item/paicard/proc/add_alert()
+	add_overlay(
+		list(mutable_appearance(icon, "[initial(icon_state)]-alert"),
+			emissive_appearance(icon, "[initial(icon_state)]-alert", alpha = src.alpha)))
+
+/obj/item/paicard/proc/remove_alert()
+	cut_overlays()
+
 /obj/item/paicard/emp_act(severity)
 	. = ..()
 	if (. & EMP_PROTECT_SELF)