Added EF and DB to the core, crude demo in the UI

WinWARP.Core/Services/Interfaces/INavigationService.cs

@@ -0,0 +1,18 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Text;
+
+namespace WinWARP.Core.Services.Interfaces;
+
+public interface INavigationService
+{
+    void NavigateTo<TViewModel>(object parameter = null) where TViewModel : class;
+    void GoBack();
+    bool CanGoBack
+    {
+        get;
+    }
+    Type CurrentViewModelType { get; }
+    event EventHandler<Type> NavigatedToViewModel;
+}