## What changed
- Record executor handshake rejections and pending-validation resets in promptly completed diagnostic spans, with classified reasons and registry HTTP status when available. Normalize stream IDs as UUIDs and cap diagnostics at 100 per minute per relay connection, followed by a suppression marker.
- Add elapsed time and connection identifiers to harness handshake diagnostics, including initialization timeouts, and classify WebSocket read failures from typed errors.
- Forward valid stream UUIDs to harness key validation requests through the `x-codex-noise-stream-id` header.
## Testing
Extend tests to cover diagnostic rate limits, timeout correlation, prompt span export, typed WebSocket error classification, and optional stream ID headers. Verify that diagnostic output excludes authorization secrets, registry response text, reset reasons, and invalid stream IDs.
GitOrigin-RevId: 2c224e2d2828b300164868b10806add410e148b2