Include kubernetes pod status phase in provider metadata

[Alphayeeeet]

Describe the enhancement:

As Cronjobs and Jobs have pod status phase lifecycle, there should be a flag for the phase like "Running", "Container creating", "Completed" etc.

Describe a specific use case for the enhancement or feature:
We try to implement annotations based autodiscovery via condition for scraping prometheus metrics. Unfortunately we have cronjobs with metrics, that complete on some point, from which on they should be ignored by the Prometheus integration. To achieve that, a condition for checking completed jobs is necessary.

What is the definition of done?

The kubernetes metadata provider should include this field. As a followup, condition checks can be built, to exclude pods that are completed.

As reference the doc, for the currently available metadata fields: https://www.elastic.co/guide/en/fleet/current/kubernetes-provider.html

[elasticmachine]

Pinging @elastic/elastic-agent-control-plane (Team:Elastic-Agent-Control-Plane)

[r4770]

We are also experiencing the need to have the pod status included in the conditions for Elastic Agent. Having access to the pod status (e.g., kubernetes.pod.status.phase) would allow us to implement more precise filtering and monitoring based on the pod's lifecycle phase.