Hello,
Welcome to Microsoft Q&A!
Yes, there is a way to bring the UWP app to the foreground. It's called CompactOverlay mode. But I don't think that is suitable for your scenario.
If you just want to let the customer know that the app is connected and it's running correctly, you could try another way by sending a local toast notification to the user. Then if the user click the notification, it could launch your app.
For more information about sending notifications, please refer to: Send a local toast notification
Thank you