Add support for deflate_options configuration

[studzien]

This PR adds support for passing deflate_options to the underlying Cowboy WebSocket adapter, allowing users to configure deflate compression settings for their WebSocket connections.

Changes

• Added deflate_options to the list of supported connection options in WebSockAdapter.upgrade/4
• Updated documentation to mention the new option
• The option is passed through to Cowboy as deflate_opts (matching Cowboy's expected parameter name)

Compatibility

This change is backwards compatible as it only adds a new optional configuration parameter.

[studzien]

Hello @mtrudel.
Is there any chance to include this (or an equivalent) soon? We still rely on Cowboy at the moment, and ideally, we don't use our own fork for production deployment (although that's going to be fine temporarily).

Thanks!

[mtrudel]

Apologies! I must have missed the original notification for this PR and it fell through the cracks! Merging right away

[mtrudel]

Released as 0.5.9. Apologies again for the extreme tardiness.

[studzien]

Thank you! No worries at all! I wasn't sure if there was a notification involved (as I couldn't add a reviewer or assignee), so I pinged you in the comment.

Thanks again! 🙏