Support request IDs in exec-server WebSocket handshakes

[copyberry]

Support request IDs in exec-server WebSocket handshakes

What changed

• Add optional websocketRequestId to environment/add and send it as X-Request-ID on direct WebSocket upgrades, including reconnects. It requires a secure transport or a loopback destination.
• Echo a supplied X-Request-ID in the exec-server WebSocket upgrade response.

Testing

Add coverage for websocketRequestId serialization and for handshake header forwarding and echoing, both with and without a request ID.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	🔄 Running since 2026-10-08T19:14:03.847415Z	b7b0a23	PR opened

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