Get desktop application:View/edit binary Protocol Buffers messages
Assume [`KeyRange`] does not overlaps.
Used in: KeyRangeInfo, WheelMeta
Used in: rudder.AddKeyRangesRequest, rudder.RouterResponse, wheel.AddKeyRangesRequest
raft group id
key range
{ raft node id -> node id }
leader raft node id Used by query router info.