Update iproto replication docs to 3.0 (#4638)

Resolves #3503, #3886

Author: p7nov

doc/reference/internals/iproto/images/repl_ballot.puml

@@ -16,7 +16,8 @@ json "**IPROTO_BALLOT body**" as ballot {
     "[[https://tarantool.io/en/doc/latest/reference/internals/iproto/keys/#general-replication IPROTO_BALLOT_IS_BOOTED]]": "MP_BOOL",
     "[[https://tarantool.io/en/doc/latest/reference/internals/iproto/keys/#general-replication IPROTO_BALLOT_CAN_LEAD]]": "MP_BOOL",
     "[[https://tarantool.io/en/doc/latest/reference/internals/iproto/keys/#general-replication IPROTO_BALLOT_BOOTSTRAP_LEADER_UUID]]": "MP_STR",
-    "[[https://tarantool.io/en/doc/latest/reference/internals/iproto/keys/#general-replication IPROTO_BALLOT_REGISTERED_REPLICA_UUIDS]]": "MP_ARRAY"
+    "[[https://tarantool.io/en/doc/latest/reference/internals/iproto/keys/#general-replication IPROTO_BALLOT_REGISTERED_REPLICA_UUIDS]]": "MP_ARRAY",
+    "[[https://tarantool.io/en/doc/latest/reference/internals/iproto/keys/#general-replication IPROTO_BALLOT_INSTANCE_NAME]]": "MP_STR"
 }
 
 @enduml

doc/reference/internals/iproto/images/repl_ballot.svg

@@ -12,6 +12,9 @@ json "**IPROTO_FETCH_SNAPSHOT**" as fetch_snapshot_request {
     "Header": {
       "[[https://tarantool.io/en/doc/latest/reference/internals/iproto/keys IPROTO_REQUEST_TYPE]]": "IPROTO_FETCH_SNAPSHOT",
       "[[https://tarantool.io/en/doc/latest/reference/internals/iproto/keys IPROTO_SYNC]]": "MP_UINT"
+    },
+    "Body": {
+      "[[https://tarantool.io/en/doc/latest/reference/internals/iproto/keys IPROTO_SERVER_VERSION]]": "MP_UINT – replica's version"
     }
 }
 

doc/reference/internals/iproto/images/repl_fetch_snapshot_request.puml

@@ -15,7 +15,8 @@ json "**IPROTO_JOIN**" as join_request {
     },
     "Body": {
       "[[https://tarantool.io/en/doc/latest/reference/internals/iproto/keys IPROTO_INSTANCE_UUID]]": "MP_STR – UUID of this instance",
-      "[[https://tarantool.io/en/doc/latest/reference/internals/iproto/keys IPROTO_SERVER_VERSION]]": "MP_UINT – replica's version"
+      "[[https://tarantool.io/en/doc/latest/reference/internals/iproto/keys IPROTO_INSTANCE_NAME]]": "MP_STR - name of this instance",
+      "[[https://tarantool.io/en/doc/latest/reference/internals/iproto/keys IPROTO_SERVER_VERSION]]": "MP_UINT – instance's version"
     }
 }