feat: zstd streaming support

[vladfrangu]

Please describe the changes this PR makes and why it should be merged:

Brings in native zstd streaming support for gateway decompression in environments that have it

That said, I'm leaving this as a draft for now, and seeing how zstd support progresses in node (specifically the backporting)

If someone wants to test it locally with their bots that have bigger payloads, you can use a script like this, after cloning this PR and building the repo

import { REST } from '@discordjs/rest';
import { CompressionMethod, WebSocketManager } from '@discordjs/ws';

const token = '';

const rest = new REST({}).setToken(token);

const manager = new WebSocketManager({
	intents: 0,
	rest,
	token,
	shardCount: 16,
	shardIds: [0],
	helloTimeout: 10_000,
	compression: CompressionMethod.ZstdNative,
});

manager.on('debug', console.log);
manager.on('error', console.error);

await manager.connect();
console.log('Connected');

Runnable with volta run --node 23 node script.mjs or whichever tool floats your boat.

Ideally we'd have some non native zstd module too but there doesn't seem to be any that exist right now 🙃

Status and versioning classification:

• Code changes have been tested against the Discord API, or there are no code changes
• I know how to update typings and have done so, or typings don't need updating

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[codecov]

Codecov Report

Attention: Patch coverage is 6.45161% with 29 lines in your changes missing coverage. Please review.

Project coverage is 38.53%. Comparing base (f6da949) to head (02175c0).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
packages/ws/src/ws/WebSocketShard.ts	0.00%	29 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #10758      +/-   ##
==========================================
- Coverage   42.60%   38.53%   -4.07%     
==========================================
  Files         262      241      -21     
  Lines       16129    14673    -1456     
  Branches     1549     1387     -162     
==========================================
- Hits         6871     5654    -1217     
+ Misses       9246     9007     -239     
  Partials       12       12              

Flag	Coverage Δ
core	0.89% <ø> (ø)
ws	35.79% <6.45%> (-0.51%)	⬇️

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Resolved.

[almeidx]

This branch is available for testing at @discordjs/[email protected]

[Renegade334]

I believe this will need to set flush: zlib.constants.ZSTD_e_flush, as the default zstd behaviour is not to flush the output buffer if the received message doesn't close the current frame.

[vladfrangu]

Last I tested this, it worked fine without that 👀

[vladfrangu]

Well, each ws message is a full payload compressed with zstd, and I've also tested this on a bot in a guild that was getting many payloads/sec with 0 issues. Coulddd you test the hypothesis please and let us know results 🙏

[Renegade334]

Looks like this applies only to the compression stream, not decompression. Ignore me! 👍