perf: improved garbage created by tweens slightly

They still do generate a lot of garbage but with boxed value pools I made the boxes reusable, it still does generate garbage through the delegate creation, gotta find a solution for them later

Engine.Systems/Tween/Helpers/Boxed.cs

@@ -0,0 +1,12 @@
+using Engine.Core;
+
+namespace Engine.Systems.Tween;
+
+public class Boxed<T> where T : struct
+{
+    public Event<Boxed<T>, BoxedValueChangedArguments> OnValueChanged { get; } = new();
+
+    public T Value { get; set; } = default;
+
+    public readonly record struct BoxedValueChangedArguments(T PreviousValue, T CurrentValue);
+}

Engine.Systems/Tween/Helpers/BoxedPool.cs

@@ -0,0 +1,14 @@
+using Engine.Core;
+
+namespace Engine.Systems.Tween;
+
+public class BoxedPool<T>(int initialCapacity = 1) : Pool<Boxed<T>>(() => new(), initialCapacity) where T : struct;
+public static class BoxedPoolExtensions
+{
+    public static Boxed<T> Get<T>(this BoxedPool<T> boxedPool, T value) where T : struct
+    {
+        Boxed<T> boxed = boxedPool.Get();
+        boxed.Value = value;
+        return boxed;
+    }
+}