Adds the Odyssey gamemode. (#18972)

https://forums.aurorastation.org/topic/20198-mission-briefing-auroras-gamemode-revolution

To-do:

- [x] Finish storyteller verbs.
- [x] Storyteller landmarks.
- [x] Proper storyteller spawning. Right now the gamemode system is
happy with just picking one storyteller and no actors.
- [x] Antagonist whitelists code.
- [x] Adding the Storyteller whitelist.
- [x] Mission map loading code.
- [x] Map in a bunch of missions.
- [ ] Storyteller adminhelps.

---------

Co-authored-by: Matt Atlas <liermattia@gmail.com>
Co-authored-by: DreamySkrell <>

code/modules/random_map/drop/droppod.dm

@@ -174,7 +174,7 @@
 	else
 		var/list/candidates = list()
 		for(var/client/player in GLOB.clients)
-			if(player.mob && istype(player.mob, /mob/abstract/observer))
+			if(player.mob && istype(player.mob, /mob/abstract/ghost/observer))
 				candidates |= player
 
 		if(!candidates.len)