Switch PyPI publish to API token authentication

Replace OIDC trusted publishing with API token auth to avoid
trusted publisher configuration issues.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: splasky

.github/workflows/publish-pypi.yaml

@@ -33,9 +33,6 @@ jobs:
   publish:
     needs: build
     runs-on: ubuntu-latest
-    environment: pypi
-    permissions:
-      id-token: write
 
     steps:
     - name: Download build artifacts
@@ -46,3 +43,5 @@ jobs:
 
     - name: Publish to PyPI
       uses: pypa/gh-action-pypi-publish@release/v1
+      with:
+        password: ${{ secrets.PYPI_API_TOKEN }}