IListener and IRadio purge (#11980)

Content.Server/Zombies/ZombieSystem.cs

@@ -132,6 +132,8 @@ namespace Content.Server.Zombies
                 return;
 
             if (_robustRandom.Prob(0.5f)) //this message is never seen by players so it just says this for admins
+                // What? Is this REALLY the best way we have of letting admins know there are zombies in a round?
+                // [automated maintainer groan]
                 _chat.TrySendInGameICMessage(uid, "[automated zombie groan]", InGameICChatType.Speak, false);
             else
                 _vocal.TryScream(uid);