ML Change Point Detection function for AI Assistant

[grabowskit]

Need an function that the AI Assistant can call for evaluating change points within metric data. The AI Assistant would like to query the data as part of its troubleshooting steps to find metrics that changed at the same time as the incident under investigation. Change Point detection would be very useful in this workflow.

Contingent on the Change Point Detection API

@dgieselaar

[elasticmachine]

Pinging @elastic/obs-knowledge-team (Team:obs-knowledge)

[elasticmachine]

Pinging @elastic/ml-ui (:ml)

[mwtyang]

cc @arisonl