Support hpkv in kv cache controller

[Jeffwan]

Pull Request Description

Support HPKV orchestration.

Related Issues

Resolves: part of #928 #948

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[Jeffwan]

Please do not review this PR. it's still in progress and I will add more test coverage and finish e2e testing

[Copilot]

Pull Request Overview

This PR adds support for HPKV orchestration by introducing new annotation constants and configuration parameters used in distributed mode.

• Adds new annotation constants for RDMA port, admin port, block size, block count, total slots, and virtual node count.
• Introduces a ClusterParams struct and helper functions (getPortAnnotation and getPositiveIntAnnotation) to parse these annotations.
• Updates the environment variables and container command configurations in both the watcher pod and cache statefulset for HPKV support.

Reviewed Changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 1 comment.

File	Description
pkg/controller/kvcache/kvcache_controller.go	Added new annotation constants for HPKV orchestration.
pkg/controller/kvcache/distributed.go	Introduced ClusterParams, updated pod env vars and command formatting to support HPKV orchestration.

Files not reviewed (1)

• go.mod: Language not supported

Comments suppressed due to low confidence (1)

pkg/controller/kvcache/distributed.go:254

• [nitpick] Consider confirming if the change from using kvCache.ObjectMeta.UID to kvCache.UID is intentional; using ObjectMeta.UID may improve clarity since it explicitly refers to the metadata object's UID.

metadataEnvVars := []corev1.EnvVar{

[DwyaneShi]

LGTM and approved