How to send replace operation on container/list level with PROTO encoding

[sachinholla]

With the new PROTO encoding scheme, how can a gNMI client send replace operation at a container or list level, where the new value contains multiple fields? Now every Update message can hold only one scalar value. If the new configuration multiple values we cannot send multiple Update messages it will match the intended replace behavior.

An example usecase is to replace all existing ipv4 addresses of an interface with a new set of addresses. With JSON_IETF encoding the client can send a replace with path = .../subinterface/ipv4/addresses and TypedValue.json_ietf_val = new address instances. But the same cannot be achieved with PROTO encoding now.