Fix downloadFile

salesbook.Maui/Platforms/Android/Core/FilePreviewService.cs

@@ -0,0 +1,11 @@
+using salesbook.Maui.Core.Interface;
+
+namespace salesbook.Maui.Core;
+
+public class FilePreviewService :IFilePreviewService
+{
+    public Task Preview(string fileName, string filePath)
+    {
+        throw new NotImplementedException();
+    }
+}