ci: add PyPI auto-publish workflow on tag push (#22)

ci: add PyPI auto-publish workflow on tag push. Refs devonartis/agentwrit#31

Author: devonartis

.github/workflows/pypi-publish.yml

@@ -0,0 +1,40 @@
+name: Publish to PyPI
+
+on:
+  push:
+    tags:
+      - "v*"
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+jobs:
+  publish:
+    name: Build & Publish to PyPI
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: astral-sh/setup-uv@v4
+        with:
+          version: "latest"
+
+      - name: Build package
+        run: uv build
+
+      - name: Verify package version matches tag
+        if: startsWith(github.ref, 'refs/tags/v')
+        run: |
+          TAG_VERSION="${GITHUB_REF#refs/tags/v}"
+          PKG_VERSION=$(grep '^version' pyproject.toml | head -1 | sed 's/.*"\(.*\)".*/\1/')
+          if [ "${TAG_VERSION}" != "${PKG_VERSION}" ]; then
+            echo "::error::Tag version (${TAG_VERSION}) does not match package version (${PKG_VERSION})"
+            exit 1
+          fi
+          echo "Version verified: ${PKG_VERSION}"
+
+      - name: Publish to PyPI
+        run: uv publish dist/*
+        env:
+          UV_PUBLISH_TOKEN: ${{ secrets.PYPI_API_TOKEN }}