## What changed
- Add opt-in runtime authentication through `ModelClient::with_runtime_auth`, requiring the provider and runtime manager to share the selected OpenAI credentials.
- Keep runtime identity, credentials, routing, and transport selection consistent for each request and its retries, signing a fresh assertion for each attempt.
- Apply authentication asynchronously to WebSocket handshakes, replace stale authentication headers, and reconnect when the runtime changes.
- Reject account, organization, or project selectors that conflict with the registered runtime, and preserve gateway OAuth composition.
## Testing
Add coverage for dual-header and assertion-only authentication, HTTP retries, runtime replacement and account switches, stale WebSocket headers, selector mismatches, gateway OAuth failures, transport revocation, and Realtime compatibility.
GitOrigin-RevId: 45b9efc2c80481406a0f6f6396a8cdd21d933c12
## What changed
Add `codex-cloud-client`, a reusable Rust client for `ThreadService.Resume` and live `ThreadService.Attach` over HTTP/2. Callers supply the native gRPC origin, bearer token, account ID, and `HttpClientFactory`.
- Reuse shared proxy, custom CA, and network policy handling for HTTPS. Reject redirects and allow plaintext HTTP only on direct loopback with unrestricted, unmanaged policy.
- Preserve notification and server-request protobuf payloads as opaque bytes and expose native gRPC status details while redacting credentials, payloads, and error details from diagnostics.
- Bound resume and attach setup to 150 seconds without retrying requests or imposing an idle deadline on live streams. Attach ends on its first error and provides no history or automatic reconnect.
- Select Rustls in `HttpClientBuilder::http2_prior_knowledge()` so HTTPS advertises `h2` through ALPN.
Include a standalone attach example and documentation of admission semantics and stream behavior.
## Testing
Add HTTP/2 fixture tests for protobuf framing, authentication metadata, status trailers, event preservation, malformed responses, stream cancellation, redirect rejection, and diagnostic redaction. Add checks for unsafe origins, network policy restrictions, and TLS `h2` advertisement.
GitOrigin-RevId: 55db70438bb5e59272c6995c67a46ced5fa28ff4
cooper-oai