## Why
Python SDK releases pin an exact `openai-codex-cli-bin` version, so all
eight platform runtime wheels must be available on PyPI before the SDK
package is built and published. PyPI does not support reusable workflows
as Trusted Publishers, which means OIDC-backed publishing must run from
each top-level release workflow.
## What changed
- add reusable `python-runtime-build.yml` to prepare and upload all
eight runtime wheels without publishing
- add top-level `python-runtime-release.yml` for manual runtime
publication before updating an SDK pin
- have `python-sdk-release.yml` publish and verify the prepared runtime
wheels from its own top-level trusted job before building the SDK
- verify PyPI exposes exactly the expected eight runtime wheels before
either release workflow continues
## PyPI configuration
- keep the trusted publisher for
`.github/workflows/python-sdk-release.yml` with environment `pypi`
- add a trusted publisher for
`.github/workflows/python-runtime-release.yml` with environment `pypi`
- no trusted publisher is needed for
`.github/workflows/python-runtime-build.yml`
## Validation
- parsed all three workflow YAML files
- validated all embedded shell blocks with `bash -n`
- no local tests run; relying on online CI