Lots of SzGui work

SzGui/Program.cs

@@ -1,6 +1,12 @@
 // See https://aka.ms/new-console-template for more information
 
+using SzCore;
+using SzCore.Defaults;
 using SzGui;
 
-var app = new SzApp();
-app.Init();
+DefaultLocalFileManager _fileManager = new();
+ISzLogger _logger = new SzLogger();
+ISzDatabaseHandler _databaseHandler = new SzDatabaseHandler();
+
+SZ.Init(_fileManager, _logger, _databaseHandler);
+SzApp.AppInstance.Init();