add workflow yml file

[NikhilShahi]

Note

Medium Risk
Adds an automated release-to-PyPI publishing workflow using OIDC, which can affect release/distribution if misconfigured (tag/version mismatch checks mitigate this).

Overview
Adds a GitHub Actions workflow (.github/workflows/publish-pypi.yml) that builds the package on release.published, validates the release tag matches pyproject.toml version, checks PyPI for an existing version, then publishes via pypa/gh-action-pypi-publish using OIDC.

Bumps the package version in pyproject.toml from 0.89.0 to 0.89.1 to align with the new release process.

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