made some improvements on how the encounters trigger

Packages/com.jovian.encounter-system/Runtime/IEncounterEvent.cs

@@ -24,4 +24,8 @@ namespace Jovian.EncounterSystem {
     public class GiveRewardEvent : IEncounterEvent {
         public Reward reward;
     }
+
+    [Serializable]
+    public class AbandonEncounterEvent : IEncounterEvent {
+    }
 }