check for existence of appsettings.json on Maui

Oqtane.Maui/MauiProgram.cs

@@ -63,6 +63,8 @@ public static class MauiProgram
     private static void LoadAppSettings()
     {
         string file = Path.Combine(FileSystem.Current.AppDataDirectory, "appsettings.json");
+        if (File.Exists(file))
+        {
             using FileStream stream = File.OpenRead(file);
             using StreamReader reader = new StreamReader(stream);
             var content = reader.ReadToEnd();
@@ -72,6 +74,7 @@ public static class MauiProgram
                 url = (string)obj["Url"];
             }
         }
+    }
 
     private static void LoadClientAssemblies(HttpClient http)
     {