Allow DYLD_* in codex's shell

What version of Codex is running?

codex-cli 0.77.0

What subscription do you have?

usage tier 5

Which model were you using?

gpt-5.1-codex

What platform is your computer?

Darwin 25.1.0 arm64 arm

What issue are you seeing?

I'm working on something where I need to set DYLD_* environment variables. It looks like the process hardening crate prevents this.

What steps can reproduce the bug?

1. prompt ! DYLD_TEST=yes env | grep DYLD_TEST
2. with shell_environment_policy.set = { DYLD_TEST = "yes" }, prompt ! echo $DYLD_TEST

What is the expected behavior?

in both cases, I expect to see DYLD_TEST set to "yes", but it is unset.

Additional information

I understand not allowing DYLD_* (or LD_PRELOAD or whatever) in codex's own processes, but not allowing them in the shell seems unreasonable. Lots of tasks depend on these tools.