Keep Codex controller turns observable

What's Changed

• Codex Agent Controller tool events now tolerate nullable numeric fields such as the in-progress exitCode instead of terminating the provider event stream and leaving a live worker permanently displayed as running.
• Individual Codex provider-message projection failures are isolated and reported while the JSON-RPC reader continues, allowing later tool and turn completion events to restore the correct idle state.

Release integrity

Native archives have matching platform-specific SPDX SBOM assets plus GitHub build-provenance and SBOM attestations. Installers and the built-in updater additionally verify a signed manifest and all packaged-file hashes.

Verification guide · Security policy