Add mob retaliation (#19901)

Content.Server/NPC/Components/FactionExceptionComponent.cs

@@ -6,12 +6,18 @@ namespace Content.Server.NPC.Components;
 /// Prevents an NPC from attacking ignored entities from enemy factions.
 /// Can be added to if pettable, see PettableFriendComponent.
 /// </summary>
-[RegisterComponent, Access(typeof(FactionExceptionSystem))]
+[RegisterComponent, Access(typeof(NpcFactionSystem))]
 public sealed partial class FactionExceptionComponent : Component
 {
     /// <summary>
-    /// List of entities that this NPC will refuse to attack
+    /// Collection of entities that this NPC will refuse to attack
     /// </summary>
     [DataField("ignored")]
     public HashSet<EntityUid> Ignored = new();
+
+    /// <summary>
+    /// Collection of entities that this NPC will attack, regardless of faction.
+    /// </summary>
+    [DataField("hostiles")]
+    public HashSet<EntityUid> Hostiles = new();
 }