zstd-stream support

[valzargaming]

https://discord.com/developers/docs/events/gateway#zstdstream
https://github.com/kjdev/php-ext-zstd
https://phpext.phptools.online/extension/zstd-334

This pull request adds support for Zstandard (zstd) compression in addition to the existing zlib compression for WebSocket payloads in the Discord client. If the ext-zstd extension is available, the client will now prefer zstd-stream compression, falling back to zlib-stream if not. The changes include dependency updates, new decompression logic, and improved logging for compression handling.

Compression support improvements:

• Added ext-zstd as a suggested dependency in composer.json for Zstandard compression support.
• Updated the Discord client to initialize and use a Zstd decompression context (ZstdContext) if the extension is available, falling back to zlib decompression otherwise. [1] [2] [3]

WebSocket message handling:

• Modified the WebSocket message handler to decompress binary payloads using Zstd if available, or zlib otherwise, and added error logging for failed decompression attempts.

Logging and diagnostics:

• Added debug logging to indicate which compression method (zstd-stream or zlib-stream) is being used during connection parameter setup.