feat: experimental zstandard support

[Phillip9587]

This PR introduces support for the Zstandard (Zstd) algorithm, which was released as an experimental feature in Node.js 23.8.0.

Key Changes

• Adds support for Zstandard (Zstd) as an optional compression algorithm.
• Can be enabled per parser middleware using the experimentalZstd option.
• Defaults to false to maintain compatibility.

Usage

To enable Zstandard in a parser middleware, set the experimentalZstd option to true:

bodyParser.json({ experimentalZstd: true })
bodyParser.raw({ experimentalZstd: true })
bodyParser.text({ experimentalZstd: true })
bodyParser.urlencoded({ experimentalZstd: true })

Notes

• This feature is experimental and subject to changes in future Node.js releases.
• Requires Node.js 23.8.0+ to function correctly.

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closes #560

[bjohansebas]

I would really prefer to wait until the API becomes stable. This is the same stance I’m going to take with compression. There may be no changes during the transition from experimental to stable, but it’s better to use only stable APIs

Great job anyway!