bug: Codex CLI crashes with sandbox-exec ENOENT on macOS if sandbox-exec is not in PATH

Question

## Bug Description

When running the Codex CLI on macOS, if the `sandbox-exec` binary is not available in the system's PATH, the tool crashes with the following error:

```
Error: spawn sandbox-exec ENOENT
```

This occurs because the CLI attempts to use the macOS Seatbelt sandbox feature (`sandbox-exec`) for security, but fails if the executable cannot be found.

## Proposed Solution

The CLI should check for the existence and executability of `sandbox-exec` before attempting to use the `MACOS_

bug: Codex CLI crashes with sandbox-exec ENOENT on macOS if sandbox-exec is not in PATH

Bug Description

Proposed Solution

Pull Request