Feature: systemd journald logging without systemd library dependency

[socketpair]

Actually, protocol is officially defined and is quite simple. It's really better to implement it in C++ directly, without extra library dependency.

https://github.com/systemd/systemd/blob/main/docs/JOURNAL_NATIVE_PROTOCOL.md
https://systemd.io/JOURNAL_NATIVE_PROTOCOL

[gabime]

Why is it better?

[socketpair]

Because it does not require third-party library. I think this tradeoff makes sense.