Add monitoring of actual functionality

[gr2m]

Follow up to #803

I have monitoring in place but only for a simple ping, the monitoring is not covering the actual functionality of the app.

I think I will utilize GitHub Actions and a dedicated repository for the monitoring. So it might not catch problems immediately but it should be good enough. I should also be able to hook it up to to test preview deployments for pull requests, which would have caught the last two outages before I even merged the pull requests