API: split pr for metrics protos

[smonero]

Description

It was requested to split this PR https://github.com/lyft/clutch/pull/2223/files to just the protos, so here they are :)

The idea here is that there will be a "metrics" service in Clutch that can get metrics from a store, such as m3 or something else. It follows a similar pattern as the diagnostics api in private. It could potentially "fan-out" to providers, as shown in the config proto. Something discussed at a meeting was that even though not necessarily all providers will have the same fields as prometheus does, it is ok for some of the fields to be blank.

Testing Performed

none needed

GitHub Issue

Fixes #

TODOs

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[smonero]

return type should be one:
provider style configuration
fanout to different providers?

enable in config section

example:
https://github.com/lyft/clutch-private/blob/main/backend/config/dash-config.yaml#L4-L9

topology uses data blob that it ingests

[github-actions]

This PR has been marked as stale after 7 or more days of inactivity. Please have a maintainer add the on hold label if this PR should remain open. If there is no further activity or the on hold label is not added, this PR will be closed in 3 days.

[github-actions]

This PR has been marked as stale after 7 or more days of inactivity. Please have a maintainer add the on hold label if this PR should remain open. If there is no further activity or the on hold label is not added, this PR will be closed in 3 days.

[github-actions]

This PR has been marked as stale after 7 or more days of inactivity. Please have a maintainer add the on hold label if this PR should remain open. If there is no further activity or the on hold label is not added, this PR will be closed in 3 days.

[danielhochman]

small nits