InitClientNotify initiates the notify send/recv.

relative to PlatformHaInstanceActiveExpireTime how long cloudletInfo cache is valid.

relative to PlatformHaInstanceActiveExpireTime how often to refresh cloudlet info.

CRMData is a wrapper around crmutil.CRMHandler and uses it in the context of the on-edge-site CRM.

ExecReqHandler just satisfies the Recv() function for the ExecRequest receive notify interface, and calls into the controller data which has all the cached information about the ClusterInst, AppInst, etc.