92ee529ce7
The action bumps in #9149 moved typegen-checks.yml to setup-uv@v8 + setup-python@v6. With that combination, uv 0.6.10 no longer falls back to the system Python, so `uv pip install --editable .` fails with "No virtual environment found for Python 3.11". Set UV_SYSTEM_PYTHON=1 at the job level, matching python-checks.yml and python-tests.yml. Also apply it to openapi-checks.yml, which is latently affected by the same issue once its actions are bumped. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>