Bug: codex exec ignores .codexrc configuration file

Bug Report

Version: codex 1.0.2
OS: Ubuntu 22.04 (GitHub Actions runner)

Description

The .codexrc configuration file in the project root is completely ignored by codex exec. Settings like model, timeout, and sandbox have no effect.

Steps to Reproduce

1. Create .codexrc with {"model": "o4-mini", "timeout": 30}
2. Run codex exec "hello world"
3. Observe it uses default model, not the one in .codexrc

Expected

Configuration from .codexrc should be respected.

Actual

All .codexrc settings are silently ignored. No warning or error.

Environment

Running in GitHub Actions with the codex-action.

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