Clown Ops war declaration plays Entry of the Gladiators (#91727)

## About The Pull Request

Does exactly what the PR title says. Also, in order to facilitate this
different sound, war ops remotes can be varedited to use an arbitrary
sound.

## Why It's Good For The Game

Come on, the thematics are obvious. A military march co-opted into
literal clown music, being used by a paramilitary special operations
team consisting entirely of clowns?

Also makes it more obvious that it's clown ops and not regular war ops,
without the need to say so in the declaration itself.

## Changelog

🆑
sound: Clown Operatives will now broadcast their declarations of war
with a fitting auditory cue.
/🆑

code/modules/antagonists/nukeop/equipment/nuclear_challenge.dm

@@ -16,6 +16,7 @@ GLOBAL_LIST_EMPTY(jam_on_wardec)
 			Must be used within five minutes, or your benefactors will lose interest."
 	var/declaring_war = FALSE
 	var/uplink_type = /obj/item/uplink/nuclear
+	var/announcement_sound = 'sound/announcer/alarm/nuke_alarm.ogg'
 
 /obj/item/nuclear_challenge/attack_self(mob/living/user)
 	if(!check_allowed(user))
@@ -80,7 +81,7 @@ GLOBAL_LIST_EMPTY(jam_on_wardec)
 	priority_announce(
 		text = memo,
 		title = "Declaration of War",
-		sound = 'sound/announcer/alarm/nuke_alarm.ogg',
+		sound = announcement_sound,
 		has_important_message = TRUE,
 		sender_override = "Nuclear Operative Outpost",
 		color_override = "red",
@@ -166,6 +167,7 @@ GLOBAL_LIST_EMPTY(jam_on_wardec)
 
 /obj/item/nuclear_challenge/clownops
 	uplink_type = /obj/item/uplink/clownop
+	announcement_sound = 'sound/announcer/alarm/clownops.ogg'
 
 /// Subtype that does nothing but plays the war op message. Intended for debugging
 /obj/item/nuclear_challenge/literally_just_does_the_message
@@ -192,7 +194,7 @@ GLOBAL_LIST_EMPTY(jam_on_wardec)
 	priority_announce(
 		text = memo,
 		title = "Declaration of War",
-		sound = 'sound/announcer/alarm/nuke_alarm.ogg',
+		sound = announcement_sound,
 		has_important_message = TRUE,
 		sender_override = "Nuclear Operative Outpost",
 		color_override = "red",

sound/announcer/alarm/attribution.txt

@@ -1,2 +1,5 @@
 airraid.ogg by Jwade722. Shortened and cut.
 https://freesound.org/people/Jwade722/sounds/534550/
+
+clownops.ogg taken from YouTube. Shortened and cut.
+https://www.youtube.com/watch?v=F0GNS6F44wE