Show instance cheat scores on admin dashboard

[bkimminich]

As an admin it would be nice to have the total cheat score per instance visible on the dashboard. This can be retrieved via the Prometheus endpoint /metrics from the juiceshop_cheat_score{app="juiceshop"} field per instance.

⚠️ This would probably solve the "Exposed Metrics" challenge for all instances if pulled from /metrics! The webhook payload also contains the current total cheat score. Other than the challenge status, the cheat score is not available via API/database but on-demand only via Prometheus endpoint.

[J12934]

Cool idea :)

It wouldn't need to solve the challenge. We already have a exclusion for requests with a Prometheus user agent. https://github.com/juice-shop/juice-shop/blob/master/routes/metrics.ts#L70