New field in `IPROTO_FETCH_SNAPSHOT` request: IPROTO_SERVER_VERSION

[TarantoolBot]

Product: Tarantool
Since: 3.0
Root document: https://www.tarantool.io/en/doc/latest/dev_guide/internals/iproto/replication/
SME: @ sergepetrenko

Details

IPROTO_FETCH_SNAPSHOT request was bodyless (only contained a header)
until now, but now it receives a body with a single field:
IPROTO_SERVER_VERSION : MP_UINT -- an encoded representation of the
server version of a replica issuing the request.
Requested by @sergepetrenko in tarantool/tarantool@58c006c.

Definition of done

• IPROTO_FETCH_SNAPSHOT description and diagrams reflect the new request body