Add PyPI publishing workflow and update license

- Created GitHub Actions workflow to build frontend and publish to PyPI
- Added license field to pyproject.toml to fix deprecation warning
- Updated .gitignore to exclude build artifacts
- Tested package building successfully

Co-authored-by: RockChinQ <45992437+RockChinQ@users.noreply.github.com>

.gitignore

@@ -47,3 +47,8 @@ uv.lock
 plugins.bak
 coverage.xml
 .coverage
+
+# Build artifacts
+/dist
+/build
+*.egg-info