## Summary
- Fixes the `handleProtocols` option not setting the selected protocol
in WebSocket upgrade responses
- Removes duplicate protocol header values in responses
## Test plan
- Added regression tests in `test/regression/issue/3613.test.ts`
- Verified using fetch to check actual response headers contain the
correct protocol
Fixes#3613🤖 Generated with [Claude Code](https://claude.com/claude-code)
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Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
