Avalonia - Save Manager (#3476)

* Add save manager to account selector

* add fallback to app metadata for titlename if app is not in gamelist

* Allow recovering lost accounts

Ryujinx.Ui.Common/App/ApplicationMetadata.cs

@@ -2,6 +2,7 @@
 {
     public class ApplicationMetadata
     {
+        public string Title { get; set; }
         public bool   Favorite   { get; set; }
         public double TimePlayed { get; set; }
         public string LastPlayed { get; set; } = "Never";