feat: add container status resource metrics from runtime state

[mrIncompetent]

What this PR does / why we need it:

The new metrics track currently applied resource limits and requests as reported by the container runtime, which may differ from pod spec during in-place resource updates.

Adds:

• kube_pod_container_status_resource_limits
• kube_pod_container_status_resource_requests
• kube_pod_init_container_status_resource_limits
• kube_pod_init_container_status_resource_requests

How does this change affect the cardinality of KSM: (increases, decreases or does not change cardinality)

Adds 4 new metric families with the same label dimensions as existing container resource metrics (container, namespace, node, pod, resource, uid, unit). The cardinality increase is proportional to the number of containers and init containers across all pods.

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[mrueg]

I believe this is a duplicate of #2702 isn't it?

[mrIncompetent]

Mostly it is, with slight differences:

• Refactoring of the ResourceList parsing (nice to have)
• This here covers init containers as well as sidecars can be resized too
• Different metric names: kube_pod_container_status_resource_requests vs kube_pod_container_actual_resource_requests

Edit:
Commented #2702 (comment)