track vf + env version in metadata

[mikasenghaas]

Description

saves vf version commit + env version and commit into the metadata of an eval run. useful to show on platform for y reasons and to match an eval run to env versions

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Test improvement

Testing

• All existing tests pass when running uv run pytest locally.
• New tests have been added to cover the changes

Checklist

• My code follows the style guidelines of this project as outlined in AGENTS.md
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• Any dependent changes have been merged and published

Additional Notes

---

Note

Medium Risk
Low-impact API extension, but it introduces subprocess calls to git during metadata construction which could behave differently across runtime environments and affect performance/timeouts.

Overview
Eval run metadata now includes a new version_info block containing the verifiers framework version/commit and the environment package version/commit.

This adds a VersionInfo type, populates it automatically in GenerateOutputsBuilder via a new version_utils helper (using package metadata and git rev-parse when available), updates test fixtures to include defaults, and documents the new metadata field in the reference docs.

^{Written by Cursor Bugbot for commit d9f2580. This will update automatically on new commits. Configure here.}