Documentation on Metrics & Tracing is missing

[Ullaakut]

Description

Currently, the documentation does not provide any resources, whether internal or external documentation, to explain how to appropriately set up metrics and tracing in Maesh.

It is possible to use Traefik's documentation on the subject (which is not linked in the Maesh doc at the moment) in order to understand how it works, but because Maesh does not provide the same configuration customization options as Traefik does, it isn't really applicable either.

This will lead to a frustrating experience for people trying to set it up, and they will potentially make mistakes because we're not giving any clue as to what the best practices are for metrics and tracing in Maesh.