- Implement `streamCodexDuplex` to handle bidirectional WebSocket interactions for Codex
- Support steering continuations (`response.steer`) and queued creations (`response.create`, `response.append`)
- Preserve response settings and state transitions across steering updates and automatic successors
- Isolate connection-level failures with `codexDuplexConnectionError` to prevent unnecessary credential cooldowns
Closes: #5968
- Add `codex.orphan-delegation-compatibility` configuration option and mirror it to SDK configuration.
- Convert orphan Codex delegation outputs into standard user messages for requests with `X-Openai-Subagent: collab_spawn`.
- Integrate orphan delegation rewriting into OpenAI responses request handling pipeline.
Closes: #5401
- Removed deprecated interceptor and executor-related methods, including `callRequestInterceptor`, `callResponseInterceptor`, and `callStreamChunkInterceptor`.
- Consolidated unused logic and pruned redundant imports to streamline `adapters.go`.
- No functional changes.
