Add project files.

WinGreedWPF/StartupHelpers/AbstractFactory.cs

@@ -0,0 +1,18 @@
+using System;
+
+namespace WinGreedWPF.StartupHelpers;
+
+public class AbstractFactory<T> : IAbstractFactory<T>
+{
+    private readonly Func<T> _factory;
+
+    public AbstractFactory(Func<T> factory)
+    {
+        _factory = factory;
+    }
+
+    public T Create()
+    {
+        return _factory();
+    }
+}