refactor: add peer_hostname field in information_schema.cluster_info table

[zyy17]

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What's changed and what's your intention?

Related greptime-proto PR: GreptimeTeam/greptime-proto#278.

Add peer_hostname field in information_schema.cluster_info table.

PR Checklist

Please convert it to a draft if some of the following conditions are not met.

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR requires documentation updates.
• API changes are backward compatible.
• Schema or data changes are backward compatible.

[killme2008]

What’s the purpose of this field? Isn’t peer_addr sufficient? @zyy17

FYI: I recommend naming the table field peer_hostname (hostname is fine in the proto).

[zyy17]

What’s the purpose of this field? Isn’t peer_addr sufficient? @zyy17

FYI: I recommend naming the table field peer_hostname (hostname is fine in the proto).

Most of the time, peer_addr will be in IP format with a port. It isn't easy to read and use.

hostname is also the key information and is human-readable. Also, the 3rd tool can use this info to fetch the monitoring data.

[zyy17]

@sunng87, I added some todo!() for the new JSON type to adapt the new proto, PTAL.

[WenyXu]

LGTM