Added Whisper system for talking with players 2 tiles away. (#5994)

Co-authored-by: metalgearsloth <comedian_vs_clown@hotmail.com>

Content.Client/Chat/ChatHelper.cs

@@ -14,7 +14,8 @@ namespace Content.Client.Chat
                 ChatChannel.OOC => Color.RoyalBlue,
                 ChatChannel.Dead => Color.MediumPurple,
                 ChatChannel.Admin => Color.Red,
-                _ => Color.DarkGray
+                ChatChannel.Whisper => Color.DarkGray,
+                _ => Color.LightGray
             };
     }
 }