Adds switch and swap into event to party.

PkmnLibSharp/Battling/PokemonParty.cs

@@ -8,6 +8,11 @@ namespace PkmnLibSharp.Battling
 {
     public class PokemonParty : PointerWrapper, IEnumerable<Pokemon?>
     {
+        public delegate void OnSwitchDelegate(ulong a, ulong b);
+        public event OnSwitchDelegate? OnSwitch;
+        public delegate void OnSwapIntoDelegate(ulong a);
+        public event OnSwapIntoDelegate? OnSwapInto;
+        
         private Pokemon?[]? _cache;
         private ReadOnlyNativePtrArray<Pokemon>? _party;
         
@@ -43,6 +48,7 @@ namespace PkmnLibSharp.Battling
             var temp = _cache![indexA];
             _cache[indexA] = _cache[indexB];
             _cache[indexB] = temp;
+            OnSwitch?.Invoke(indexA, indexB);
         }
 
         public Pokemon? SwapInto(ulong indexA, Pokemon? pokemon)
@@ -52,6 +58,7 @@ namespace PkmnLibSharp.Battling
             if (pokemon != null) pkmnPtr = pokemon.Ptr;
             Creaturelib.Generated.CreatureParty.SwapInto(ref ptr, Ptr, indexA, pkmnPtr).Assert();
             _cache![indexA] = pokemon;
+            OnSwapInto?.Invoke(indexA);
             if (TryResolvePointer(ptr, out Pokemon? newPokemon))
                 return newPokemon!;
             return Constructor.Active.ConstructPokemon(ptr)!;