Provide a supported option to enable/disable etcd defragmentation process on nonHA (SNO) use cases.

1. Proposed title of this feature request
Provide a supported option to enable/disable etcd defragmentation process on nonHA (SNO) use cases.

2. What is the nature and description of the request?
Curently there is hardcoded defragmentation exceptions for non-HA topologies [1](e.g., SNO). The assumption does not fit all customer using non-HA topologies.

Consider exposing a configMap or any othjer option on the CR for nonHA use cases
Explore the option for conditional defragmentation (e.g., automatic defragmentation when db fragmentation is above certain threshold and db size is over certain size)

[1] https://github.com/openshift/cluster-etcd-operator/blob/master/pkg/operator/defragcontroller/defragcontroller.go#L106-L110

3. Why does the customer need this? (List the business requirements here)
non-HA topologies, or Single-node OpenShift, are targeted for airgapped and self-contained deployments where manual interventions are minimal due lack of stable connectivity or regulations in place. OpenShift must be as much autonomous as possible in such deployments.

4. List any affected packages or components.
Single-Node OpenShift
etcd cluster operator