* fix: webpack browser build - use UMD dist/less.js, add CJS bundle (#4423)
- Browser exports point to dist/less.js (UMD) instead of less-node
- Add CJS bundle (dist/less-node.cjs) for Node require() with module shim
- Remove dead index.js; index.cjs re-exports CJS bundle
- Add export tests: import-patterns, webpack-browser, test-cjs-suite
- CI and publish workflows run test:node (build + CJS + ESM tests)
* Beta publish script
* chore: clarify test:node runs ESM + CJS in workflow labels
* fix: normalize path separators in rollup plugin for Windows CI
The inlinePackageVersion plugin used forward-slash path check that
failed on Windows where rollup passes backslash-separated IDs,
leaving the require('../../package.json') unresolved at runtime.
* chore: bump version to 4.6.3 for release
