feature: add consumption metrics to sync-agent

[SimonTheLeg]

The following custom metrics should be added to our sync-agent. Ideally these are part of the already existing metrics scraping endpoint.

• sync_agent_published_resource → Counter of the current number of published resources managed by the agent.

[xrstf]

sync_agent_logicalcluster_watch → Counter of logicalclusters the sync_agent is watching for ressources to sync

I wouldn't know how this can be implemented efficiently, based on how we're watching resources. I don't think we should begin to just watch LogicalCluster objects mere to see how many folks have bound the API we're serving.

[SimonTheLeg]

I wouldn't know how this can be implemented efficiently, based on how we're watching resources. I don't think we should begin to just watch LogicalCluster objects mere to see how many folks have bound the API we're serving.

Yeah I had an error in my thinking on this. It's true it would not make sense because we would have to query for logicalclusters through the ApiExport VW and this request would get increasingly larger with the number logicalclusters.
I have removed the metric