ruff

0bb8cbdf - [ty] Do not allow invalid virtual environments from discovered `.venv` or `VIRTUAL_ENV` (#18003)

[ty] Do not allow invalid virtual environments from discovered `.venv` or `VIRTUAL_ENV` (#18003) Follow-up to https://github.com/astral-sh/ruff/pull/17991 ensuring we do not allow detection of system environments when the origin is `VIRTUAL_ENV` or a discovered `.venv` directory — i.e., those always require a `pyvenv.cfg` file.