NPC refactor (#10122)

Co-authored-by: metalgearsloth <metalgearsloth@gmail.com>

Content.Shared/NPC/HTNMessage.cs

@@ -0,0 +1,13 @@
+using Robust.Shared.Serialization;
+
+namespace Content.Shared.NPC;
+
+/// <summary>
+/// Has debug information for HTN NPCs.
+/// </summary>
+[Serializable, NetSerializable]
+public sealed class HTNMessage : EntityEventArgs
+{
+    public EntityUid Uid;
+    public string Text = string.Empty;
+}