Expand prometheus metrics coverage to include custom route-based metrics

[filvecchiato]

Proposed Change or Idea

Currently the prometheus metrics expose standard metrics for all HTTP routes, and the metrics Class has a function to emit route-based metrics as well. Could be interesting to inject the metrics registry in the Route Controllers and have the specific controller emit custom metrics route based, encapsulating the metrics behaviour within the controller itself

Alternatives

A possibly simpler solution is to have route-based function resolvers within the Metrics Class