Setup Onionprobe visualizations for TPO

Description

Setup Onionprobe visualizations for TPO in the Prometheus or Grafana dashboard.

Tasks

• Coordinate with Hiro and TPA to deploy the Onionprobe monitoring/dashboard on grafana2.
• Need a Onionprobe instance somewhere we can easily update the config file and restart the service; and installed in a way that's flexible for us to update and test things (so maybe not as a Debian package).
• No need to restrict monitoring to TPO onionsites if categories are supported.
• Could be public dashboard hosted in an isolated Onionprobe standalone instance: https://grafana.com/docs/grafana/latest/dashboards/dashboard-public/
• Maybe retire the other instance set on tpo/tpa/team#40717 (closed), if it's not being used (to save resources and reduce things to be maintained).
• Use the Onionsphere list for monitoring.

Time estimation

• Complexity: medium (3 days)
• Uncertainty: low (x1.1)
• Reference (adapted)