Support distributed hashing mode kv cache pool

[Jeffwan]

Pull Request Description

Support distributed hashing mode kv cache pool

Related Issues

Resolves: part of #928

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[Copilot]

Pull Request Overview

This PR adds support for distributed hashing mode with a KV cache pool by introducing new reconciliation logic for stateful sets, watcher pods, and redis services. Key changes include:

• New constants and RBAC rules to support KV cache watcher and stateful set objects.
• Implementation of functions for reconciling stateful sets, watcher pods, and redis-related resources.
• Updates to CRD defaults and types to support pointer-based storage fields.

Reviewed Changes

Copilot reviewed 8 out of 10 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
pkg/controller/kvcache/kvcache_controller.go	Added new constants and functions to reconcile stateful sets.
pkg/controller/kvcache/distributed.go	Introduced distributed mode functions, watcher pod, and redis logic.
pkg/controller/kvcache/centralized.go	Updated metadata service reconciliation to invoke redis support.
config/rbac/controller-manager/role.yaml	Added RBAC rules for stateful sets and their status updates.
config/crd/orchestration/orchestration.aibrix.ai_kvcaches.yaml	Updated CRD defaults and removal of extra required fields.
cmd/kvcache-watcher/main.go	New watcher binary implementation for registering pod events.
api/orchestration/v1alpha1/zz_generated.deepcopy.go	Adjusted deepcopy logic for pointer types in storage fields.
api/orchestration/v1alpha1/kvcache_types.go	Updated storage type in RedisConfig and EtcdConfig to pointer types.

Files not reviewed (2)

• Makefile: Language not supported
• build/container/Dockerfile.kvcache: Language not supported

Comments suppressed due to low confidence (1)

pkg/controller/kvcache/distributed.go:230

• The variable name 'statfulset' appears to be a typo. It should be renamed to 'statefulset' for clarity.

statfulset := &appsv1.StatefulSet{

[Copilot]

The watcher pod is being labeled with KVCacheLabelValueRoleMetadata instead of using the dedicated watcher role. Consider using KVCacheLabelValueRoleKVWatcher to clearly identify watcher pods.

Suggested change

	KVCacheLabelKeyRole: KVCacheLabelValueRoleMetadata,
	KVCacheLabelKeyRole: KVCacheLabelValueRoleKVWatcher,

[Jeffwan]

resolved. nice catch

[Jeffwan]

Due to limited reviewers this week. I will merge this request