This introduces `./codex-cli/scripts/stage_release.sh`, which is a shell
script that stages a release for the Node.js module in a temp directory.
It updates the release to include these native binaries:
```
bin/codex-linux-sandbox-arm64
bin/codex-linux-sandbox-x64
```
though this PR does not update Codex CLI to use them yet.
When doing local development, run
`./codex-cli/scripts/install_native_deps.sh` to install these in your
own `bin/` folder.
This PR also updates `README.md` to document the new workflow.
---
[//]: # (BEGIN SAPLING FOOTER)
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with [ReviewStack](https://reviewstack.dev/openai/codex/pull/757).
* #763
* __->__ #757
Michael Bolin