Bump version to 0.6.1

[Copilot]

Sync lfpykit/version.py to 0.6.1 to match pyproject.toml and trigger the GitHub Actions release pipeline for test-PyPI and PyPI.

Description

• Bumped lfpykit/version.py from "0.6.0" to "0.6.1" — pyproject.toml was already at 0.6.1

Related Issue

Resolves version mismatch between version.py and pyproject.toml.

Motivation and Context

pyproject.toml had already been updated to 0.6.1, but lfpykit/version.py was still at 0.6.0. The release workflows key off the version in version.py, so the new release was not being triggered.

How Has This Been Tested

No functional code changes; version string update only.

Types of changes

• Docs change / refactoring / dependency upgrade

Checklist

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.