Allow configuring redis-ha-haproxy replica count via spec.ha.replicas

[preetma-redhat]

Summary

After enabling spec.ha.enabled: true, the Argo CD operator creates argocd-redis-ha-haproxy but does not expose a CR field to set the HAProxy replica count. Users cannot increase HAProxy replicas through the ArgoCD CR, and manual scaling of the Deployment is reverted by the operator.

The Redis HA StatefulSet should remain at 3 replicas for Sentinel quorum. This request is only for the HAProxy Deployment.

Motivation

Related work already aligned the default HAProxy replica count with Redis HA (3). The remaining gap is making that count user-configurable.

Upstream/community RFE: https://redhat.atlassian.net/browse/RFE-7314

Proposed API

spec:
  ha:
    enabled: true
    replicas: 5

• spec.ha.replicas controls argocd-redis-ha-haproxy only
• Default remains 3 when the field is omitted
• Redis HA server replicas stay at 3

Reproduction

1. Create an ArgoCD CR with spec.ha.enabled: true
2. Observe argocd-redis-ha-haproxy at 3 replicas
3. Patch spec.ha.replicas: 5 — field is currently unknown
4. kubectl scale deploy argocd-redis-ha-haproxy --replicas=5 is immediately reverted to 3