This PR expands `.github/workflows/rust-release.yml` so that it also
builds and publishes the `npm` module for
`@openai/codex-responses-api-proxy` in addition to `@openai/codex`. Note
both `npm` modules are similar, in that they each contain a single `.js`
file that is a thin launcher around the appropriate native executable.
(Since we have a minimal dependency on Node.js, I also lowered the
minimum version from 20 to 16 and verified that works on my machine.)
As part of this change, we tighten up some of the docs around
`codex-responses-api-proxy` and ensure the details regarding protecting
the `OPENAI_API_KEY` in memory match the implementation.
To test the `npm` build process, I ran:
```
./codex-cli/scripts/build_npm_package.py --package codex-responses-api-proxy --version 0.43.0-alpha.3
```
which stages the `npm` module for `@openai/codex-responses-api-proxy` in
a temp directory, using the binary artifacts from
https://github.com/openai/codex/releases/tag/rust-v0.43.0-alpha.3.
As promised on https://github.com/openai/codex/discussions/1405, we are
making the first official release of the Rust CLI as v0.2.0. As part of
this move, we are making it available in Homebrew:
https://github.com/Homebrew/homebrew-core/pull/228615
Ultimately, we also plan to continue to make the CLI available in npm,
as well, though brew is a bit nicer in that `brew install` will download
only the binary for your platform whereas an npm module is expected to
contain the binaries for _all_ supported platforms, so it is a bit more
heavyweight.
A big part of this change is updating the root `README.md` to document
the behavior of the Rust CLI, which differs in a number of ways from the
TypeScript CLI. The existing `README.md` is moved to
`codex-cli/README.md` as part of this PR, as it is still applicable to
that folder.
As this is still early days for the Rust CLI, I encourage folks to
provide feedback on the command line flags and configuration options.
