setCookie doesn't work in awsLambda streaming

[mckamyk]

Which project does this relate to?

Start

Describe the bug

Reproduction Repo

NOTE: it appears setHeader(...) works fine with this setup.

When I have the following options in my app.config.ts...

server: {
  preset: 'aws-lambda',
  awsLambda: {
    streaming: true
  }
}

setCookie doesn't work. Looking in network devtools, the response from the server function does not have set-cookie header.

I've spun up both

• streaming example
• non-streaming example

Your Example Website or App

https://stream-test.mckamyk.io

Steps to Reproduce the Bug or Issue

1. Go to https://stream-test.mckamyk.io
2. Click "Set the Cookie"
3. the text after Cookie: on the page should update to a timestamp
4. Check the network tools, find the POST request for the ServerFn call, there should be a set-cookie header

Expected behavior

setCookie(...) should work with preset: 'aws-lambda' and awsLambda.streaming: true

Screenshots or Videos

Platform

• OS: macOS, deployed to AWS Lambda with streaming
• Browser: Tested on Chrome, Firefox (Zen). Should affect all browsers.
• Version: 1.114.23

Additional context

No response

[mckamyk]

I created a nitro issue, as it seems it is related to that.
nitrojs/nitro#3228

[mckamyk]

I created a PR in nitro to solve this
nitrojs/nitro#3236