Summary

• add the ci environment to the examples job that consumes secrets.OPENAI_API_KEY
• keep the environment scoped to the only workflow job that needs OPENAI_API_KEY
• update the runnable sync/async examples to use the current README chat model path so the CI key can exercise them

Validation

• ruby -r psych -e 'Psych.load_file(".github/workflows/ci.yml"); puts "ci.yml parsed"'
• python -m py_compile examples/demo.py examples/async_demo.py
• git diff --check

Notes

• A fork-based PR could not access secrets (Secret source: None), so this PR uses an in-repo branch for the environment-backed secret check.
• After adding the ci environment, the examples job received OPENAI_API_KEY and then exposed the legacy gpt-4 access failure; the examples now match the README model.