Add support for `zstd` Compression Algorithm to `@lune/serde`

[SnorlaxAssist]

Summary

Zstandard is a fast lossless compression algorithm, targeting real-time compression scenarios at zlib-level and better compression ratios. ...Read more

Benefits

• Expands the possible compression algorithms in serde.
• Allows to mimic Roblox's compression/decompression with buffers (link).
• Highly performant.
• High compression ratio.
• Roughly Modern.

  Considerations

  It would be nice if lune could also have a way to control the level of compression or speed using the zstd level options, in Luau.

  Alternative

• Use Lune process lib to execute zstd binaries to compress and decompress.

[filiptibell]

I was a bit hesitant on zstd before since there is no pure rust library for it, meaning we need to link another c library, but Roblox already using it in various places is a good argument for Lune also having it. I think the benefits outweigh the costs here.

This should be very straightforward to add, just enabling the zstd feature in async-compression and adding a new match branch, so if any new contributor wants to pick this up as a first issue feel free :)