refactor: change json-rpc trait names, relax bounds

[prestwich]

Motivation

Make the RPC trait system more clear and flexible, provide non-owned options requirements baked into the traits

Solution

• Rename RpcParam to RpcSend and RpcReturn to RpcReceive to make them clearer
• Add lifetimed versions of RpcReturn and RpcObject to allow borrowing from deserializers
• relax many bounds from RpcObject to either RpcBorrow or RpcSend, e.g. in ResponsePayload::serialize_payload we can relax to RpcSend

Note

The implementation of RpcRecv is still more strict than DeserializeOwned, as it requires + 'static rather than for<'de> Deserialize<'de>. This means that it is not iplemented on (e.g.) things that borrow from some non-deserializer context or environment during deserialization. Some parts of our future and streaming systems rely on this, and it seems like just marginal benefit to change

PR Checklist

• Added Tests
• Added Documentation
• Breaking changes

[mattsse]

seems okay to me, I actually prefer send/recv over param/return

any objections @DaniPopes @klkvr ?

all of this is internal, so I expect the impact of this to be minimal