[Task]: Revisit client interceptors

[ishymko]

Client-side interceptors are only implemented for JSON-RPC transport (jsonrpc.py) and the data model itself is defined around JSON-RPC and not in a transport-agnostic way: middleware.py.

REST contains a no-op function (rest.py) and there is nothing in grpc.py.

For 1.0 breaking release there is a chance to do it at the client level in a transport agnostic way. Current implementation is likely a leftover from pre-multitransport era.