[WIP] Use recvmmsg for improved UDP performance

[Copilot]

Thanks for asking me to work on this. I will get started on it and keep this PR's description up to date as I form a plan and make progress.

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This section details on the original issue you should resolve

<issue_title>UDP performance</issue_title>
<issue_description>Use recvmmsg instead of recvfrom for udp message receiving for improved performance.

I suggest using socket2 alongside the code in this issue rust-lang/socket2#493, replace the existing udp implementation for higher performance on linux. On operating systems where recvmmsg is not supported continue to use the current implementation.

See also:

• https://github.com/sebastiencs/rustorrent/blob/6829a99fb94a4badc948533f4fc75a9f0e4a32c2/src/utp/udp_socket.rs
• Improve Vector's throughput for UDP protocols vectordotdev/vector#8518

</issue_description>

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