## What changed
Add `codex tcp-tunnel` and the `codex-tcp-tunnel` crate to forward loopback TCP connections to an explicit target through a TLS-verified HTTP/3 CONNECT proxy.
- Require the proxy origin to match an approved HTTPS origin in a supplied policy file.
- Read bearer tokens and optional bounded, non-forwarding `x-` headers from stdin. Support token updates for new connections, `LISTENING` and `AUTH_UPDATED` notifications, and shutdown when the control pipe closes in token-update mode.
- Preserve the listener across proxy reconnects without replaying TCP streams, and let accepted streams continue while a proxy drains.
## Testing
Add tests for hidden CLI parsing, proxy and target validation, credential renewal, control-pipe closure, and invalid input without secret disclosure. A local HTTP/3 proxy test covers token replacement, transport recovery without stream replay, and graceful draining.
GitOrigin-RevId: c6af3025301c61e9fe90940cf5a6df0039465e69
2aff7208fe