## Why
Remote compaction currently sends a unary `POST /responses/compact` and
waits for the full response before replacing history or emitting the
completed `ContextCompaction` item. Unlike normal `/responses` streaming
requests, this unary compact request had no timeout boundary. If the
backend accepts the request and then stalls before returning a body, the
existing request retry policy never sees a transport error, so the
compact turn can remain stuck after the started item with no completion
or actionable error.
That matches the reported hang shape in issues such as #18363, where
logs show `responses/compact` was posted but no corresponding compact
completion followed. A bounded request timeout gives the existing retry
policy a concrete timeout error to retry instead of letting the user sit
indefinitely on automatic context compaction.
## What
- Add a request timeout to legacy `/responses/compact` calls.
- Size that timeout from the provider stream idle timeout with a
conservative multiplier, so the default compact attempt gets 20 minutes
rather than the 5 minute stream idle window.
- Map API transport timeouts to a request timeout error instead of the
child-process timeout message.
## Testing
- Not run (per request; CI will cover).
## Summary
- Add `codex-model-provider` as the runtime home for model-provider
behavior that does not belong in `codex-core`, `codex-login`, or
`codex-api`.
- The new crate wraps configured `ModelProviderInfo` in a
`ModelProvider` trait object that can resolve the API provider config,
provider-scoped auth manager, and request auth provider for each call.
- This centralizes provider auth behavior in one place today, and gives
us an extension point for future provider-specific auth, model listing,
request setup, and related runtime behavior.
## Tests
Ran tests manually to make sure that provider auth under different
configs still work as expected.
---------
Co-authored-by: pakrym-oai <pakrym@openai.com>
## Summary
- Move auth header construction into the
`AuthProvider::add_auth_headers` contract.
- Inline `CoreAuthProvider` header mutation in its provider impl and
remove the shared header-map helper.
- Update HTTP, websocket, file upload, sideband websocket, and test auth
callsites to use the provider method.
- Add direct coverage for `CoreAuthProvider` auth header mutation.
## Testing
- `just fmt`
- `cargo test -p codex-api`
- `cargo test -p codex-core
client::tests::auth_request_telemetry_context_tracks_attached_auth_and_retry_phase`
- `cargo test -p codex-core` failed on unrelated/reproducible
`tools::handlers::multi_agents::tests::multi_agent_v2_followup_task_interrupts_busy_child_without_losing_message`
---------
Co-authored-by: Celia Chen <celia@openai.com>
