Admin improvements for Looc and Deadchat (#41273)

* looc and deadchat speak interrupt events

* comment

* admin log tweak

* clean up log entity targets; switch admin deadchat logged entity from player to mob

* one event only

* rename event, broadcast player session with the event

Content.Shared/Chat/InGameOocMessageAttemptEvent.cs

@@ -0,0 +1,9 @@
+using Robust.Shared.Player;
+
+namespace Content.Shared.Chat;
+
+/// <summary>
+/// Event fired before a player's entity speaks on LOOC or Deadchat.
+/// </summary>
+[ByRefEvent]
+public record struct InGameOocMessageAttemptEvent(ICommonSession Session, InGameOOCChatType Type, bool Cancelled = false);