feature: add env variables for Kubernetes service

[MehdiRtal]

What type of PR is this?

/kind feature

What this PR does / why we need it:

The Problem: When a Pod is running in hostNetwork: true mode, it inherits the network namespace of the host. By default, Kubernetes injects KUBERNETES_SERVICE_HOST and KUBERNETES_SERVICE_PORT pointing to the internal ClusterIP of the API server. In certain Azure networking topologies (or when using specific local proxies), these default values can be unreachable or conflict with host-level services.

The Fix: This PR introduces the ability to specify custom values for these variables. This ensures that host-networked components (like the Azure Cloud Controller Manager or Node-level agents) can reliably reach the API server via a specific endpoint (e.g., a Load Balancer IP or localhost) rather than the default ClusterIP.

Which issue(s) this PR fixes:

NONE

Special notes for your reviewer:

Does this PR introduce a user-facing change?

Allows overriding KUBERNETES_SERVICE_HOST and KUBERNETES_SERVICE_PORT for components running in hostNetwork mode to improve connectivity in complex Azure networking environments.

[k8s-ci-robot]

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[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: MehdiRtal
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