Release 2.6.7: refresh deps and lockfile (#83)

## Summary

Bumps `agentscore-py` to 2.6.7. `uv lock --upgrade` refreshed dev
tooling within constraints (coverage 7.16.0, ty 0.0.76) with no
prereleases (the `prerelease = "disallow"` guard held), on top of the
already-merged osv-scanner v2.5.1 and minor-patch group. The uv.lock
own-version is synced to 2.6.7. Actions are current (setup-uv v10.0.1,
pypi-publish v1.14.2 both latest).

## Type of change

- [ ] Bug fix (no breaking change)
- [ ] New feature (no breaking change)
- [ ] Breaking change (existing callers must update)
- [x] Docs, tests, or internal maintenance only

## Public API

None. No exported symbols, signatures, or wire formats changed; runtime
dependencies are unchanged.

## Test plan

Ran `uv run ruff check`, `uv run ty check`, and `uv run pytest`: all
clean, 183 passed (8 skipped), 100% coverage. No behavior change, so no
new tests.

## Checklist

- [x] Tests cover the new behavior, and the suite passes locally
- [x] Lint, format, and type checks pass
- [x] Docs and README examples updated if the public surface changed
- [x] No secrets, credentials, or personal data in the diff or the tests

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

Author: vvillait88

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "agentscore-py"
-version = "2.6.6"
+version = "2.6.7"
 description = "Python client for the AgentScore APIs"
 readme = "README.md"
 license = "MIT"