[Stack Monitoring] Locator API

[cachedout]

This issue is a continuation of an issue raised in #42621.

Stack Monitoring should expose an API which can be consumed by other Kibana applications which can:

• Return an answer about whether or not the Stack Monitoring application enabled.
• Generate a URL to the correct Monitoring Node Overview page link given a Elasticsearch cluster UUID and node UUID.

[cachedout]

This is a desired feature to enable the ES Management UI, described in their Tasks UI roadmap issue.

[chrisronline]

This might be a good opportunity for you @cachedout to dive more into the Kibana code!

[alisonelizabeth]

@cachedout FYI we decided not to create the tasks UI so this feature is no longer needed by the ES UI team.

[cachedout]

@alisonelizabeth Thanks for the update. I'll close this as well then.