replace v6 with experimental v7 code

src/MpvNet/ExtensionLoader.cs

@@ -0,0 +1,41 @@
+
+using System.Reflection;
+
+using MpvNet.ExtensionMethod;
+
+namespace MpvNet;
+
+public class ExtensionLoader
+{
+    public event Action<Exception>? UnhandledException;
+
+    readonly List<object?> _refs = new();
+
+    void LoadDll(string path)
+    {
+        if (!File.Exists(path))
+            return;
+
+        try
+        {
+            Assembly asm = Assembly.LoadFile(path);
+            var type = asm.GetTypes().Where(typeof(IExtension).IsAssignableFrom).First();
+            _refs.Add(Activator.CreateInstance(type));
+        }
+        catch (Exception ex)
+        {
+            UnhandledException?.Invoke(ex);
+        }
+    }
+
+    public void LoadFolder(string path)
+    {
+        if (Directory.Exists(path))
+            foreach (string dir in Directory.GetDirectories(path))
+                LoadDll(dir.AddSep() + Path.GetFileName(dir) + ".dll");
+    }
+}
+
+public interface IExtension
+{
+}