feat(ws_transport): add header callback hook (IDFGH-15479)

[bryghtlabs-richard]

Description

Add a callback for each line of header responses in the Websocket HTTP->WS transport upgrade. This is necessary to support AWS ALB and F5 cookie-based load-balancer sticky-sessions.

Related

Please see espressif/esp-protocols#715 . There is another part of this patchset espressif/esp-protocols#827, as well as a different implementation espressif/esp-protocols#794

Testing

• Existing "Sec-WebSocket-Accept" header-parsing was tested by connecting to a websocket. Failure was tested by intentionally setting server_key = NULL and confirming we still reject the connection.
• New headers were tested by logging each header-line with ESP_LOGI() at the next layer up, in the esp_websocket_client.

---

Checklist

Before submitting a Pull Request, please ensure the following:

• 🚨 This PR does not introduce breaking changes.
• All CI checks (GH Actions) pass.
• Documentation is updated as needed.
• Tests are updated or added as necessary.
• Code is well-commented, especially in complex areas.
• Git history is clean — commits are squashed to the minimum necessary.

[github-actions]

	Messages
📖	🎉 Good Job! All checks are passing!

👋 Hello bryghtlabs-richard, we appreciate your contribution to this project!

---

📘 Please review the project's Contributions Guide for key guidelines on code, documentation, testing, and more.

---

🖊️ Please also make sure you have read and signed the Contributor License Agreement for this project.

---

Click to see more instructions ...

This automated output is generated by the PR linter DangerJS, which checks if your Pull Request meets the project's requirements and helps you fix potential issues.

DangerJS is triggered with each push event to a Pull Request and modify the contents of this comment.

Please consider the following:
- Danger mainly focuses on the PR structure and formatting and can't understand the meaning behind your code or changes.
- Danger is not a substitute for human code reviews; it's still important to request a code review from your colleagues.
- To manually retry these Danger checks, please navigate to the Actions tab and re-run last Danger workflow.

Review and merge process you can expect ...

We do welcome contributions in the form of bug reports, feature requests and pull requests via this public GitHub repository.

This GitHub project is public mirror of our internal git repository

1. An internal issue has been created for the PR, we assign it to the relevant engineer.
2. They review the PR and either approve it or ask you for changes or clarifications.
3. Once the GitHub PR is approved, we synchronize it into our internal git repository.
4. In the internal git repository we do the final review, collect approvals from core owners and make sure all the automated tests are passing.
- At this point we may do some adjustments to the proposed change, or extend it by adding tests or documentation.
5. If the change is approved and passes the tests it is merged into the default branch.
5. On next sync from the internal git repository merged change will appear in this public GitHub repository.

Generated by 🚫 dangerJS against 0245c5c

[glmfe]

sha=0245c5c863fd1bf08ed9fbd913f8cccb297948cc

[euripedesrocha]

sha=0245c5c863fd1bf08ed9fbd913f8cccb297948cc