Prevent autosay() from creating/deleting AIs

Now it gets one dedicated AI it can move around instead.

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

@@ -247,14 +247,12 @@ var/global/list/default_medbay_channels = list(
 	if (!connection)
 		return
 
-	var/mob/living/silicon/ai/A = new /mob/living/silicon/ai(src, null, null, 1)
+	var/static/mob/living/silicon/ai/announcer/A = new /mob/living/silicon/ai/announcer(src, null, null, 1)
 	A.SetName(from)
 	Broadcast_Message(connection, A,
 						0, "*garbled automated announcement*", src,
 						message, from, "Automated Announcement", from, "synthesized voice",
 						4, 0, list(0), connection.frequency, "states")
-	qdel(A)
-	return
 
 // Interprets the message mode when talking into a radio, possibly returning a connection datum
 /obj/item/device/radio/proc/handle_message_mode(mob/living/M as mob, message, message_mode)