Use RetryOnConflict on Status().Update calls

[mpryc]

Optimistic concurrency control in k8s is separate for Spec and Status fields. We should use RetryOnConflict and get updated version of the object.

Sample implementation idea:

func (r *NonAdminBackupReconciler) updateStatusWithRetry(
    ctx context.Context,
    logger logr.Logger,
    nab *nacv1alpha1.NonAdminBackup,
    newPhase *nacv1alpha1.NonAdminBackupPhase,
    newCondition *metav1.Condition,
) (bool, error) {
    var updated bool

    err := retry.RetryOnConflict(retry.DefaultRetry, func() error {
        // Try to update with our current version first
        if newPhase != nil {
            updated = updateNonAdminPhase(&nab.Status.Phase, *newPhase) || updated
        }
        if newCondition != nil {
            updated = meta.SetStatusCondition(&nab.Status.Conditions, *newCondition) || updated
        }

        if !updated {
            return nil
        }

        updateErr := r.Status().Update(ctx, nab)
        if !apierrors.IsConflict(updateErr) {
            return updateErr // Either nil or non-conflict error
        }

        // Only fetch the latest version if we hit a conflict
        if err := r.Get(ctx, types.NamespacedName{Name: nab.Name, Namespace: nab.Namespace}, nab); err != nil {
            return err
        }

        // Reapply our changes to the fresh copy
        if newPhase != nil {
            updated = updateNonAdminPhase(&nab.Status.Phase, *newPhase)
        }
        if newCondition != nil {
            updated = meta.SetStatusCondition(&nab.Status.Conditions, *newCondition) || updated
        }

        return r.Status().Update(ctx, nab)
    })

    if err != nil {
        logger.Error(err, statusUpdateError)
        return false, err
    }

    return updated, nil
}