Modify admin chat (#13050)

* split admin chat into new channel

* add ability to play audio when a chat message is received and add audio to admin chat

* give client control of AdminChat sound and volume + suppress sound for senders

Content.Client/UserInterface/Systems/Chat/Controls/ChannelFilterPopup.xaml.cs

@@ -20,6 +20,7 @@ public sealed partial class ChannelFilterPopup : Popup
         ChatChannel.OOC,
         ChatChannel.Dead,
         ChatChannel.Admin,
+        ChatChannel.AdminChat,
         ChatChannel.Server
     };
 

Content.Client/UserInterface/Systems/Chat/Controls/ChannelSelectorButton.cs

@@ -82,7 +82,7 @@ public sealed class ChannelSelectorButton : Button
             ChatSelectChannel.LOOC => Color.MediumTurquoise,
             ChatSelectChannel.OOC => Color.LightSkyBlue,
             ChatSelectChannel.Dead => Color.MediumPurple,
-            ChatSelectChannel.Admin => Color.Red,
+            ChatSelectChannel.Admin => Color.HotPink,
             _ => Color.DarkGray
         };
     }