PR 5.4: Enable Cluster-capable clients

[KurodaKayn]

What to build

Make the application Redis clients Cluster-ready while preserving the ability to run in the current managed HA standalone mode. Client configuration should cover Cluster topology discovery, MOVED and ASK redirects, topology refresh, retry behavior, TLS, auth, and rollback to standalone mode.

Acceptance criteria

• Redis client configuration can select standalone managed HA mode or Cluster mode without code changes.
• Cluster mode handles MOVED and ASK redirects, topology refresh, retries, TLS, and auth according to the selected provider requirements.
• Integration tests verify the app can read and write through Cluster-capable clients against a Cluster-compatible environment.
• Standalone managed HA mode remains the rollback path and is still covered by tests or smoke checks.

Blocked by

• PR 5.3: Replace or constrain cross-slot operations #347