Move all battle state from IPokemon to an ephemeral IBattlePokemon wrapper

PkmnLib.Dynamic/Events/FleeEvent.cs

@@ -8,7 +8,7 @@ namespace PkmnLib.Dynamic.Events;
 public class FleeEvent : IEventData
 {
     /// <inheritdoc cref="FleeEvent"/>
-    public FleeEvent(IPokemon pokemon, bool success)
+    public FleeEvent(IBattlePokemon pokemon, bool success)
     {
         Pokemon = pokemon;
         Success = success;
@@ -17,7 +17,7 @@ public class FleeEvent : IEventData
     /// <summary>
     /// The Pokémon that attempted to flee.
     /// </summary>
-    public IPokemon Pokemon { get; }
+    public IBattlePokemon Pokemon { get; }
 
     /// <summary>
     /// Indicates whether the flee attempt was successful.