Add bootstrap-icons npm package with SCSS import and font file copy
build step. All 2,000+ icons available via CSS classes (bi bi-*) in
both frontend and block editor.
Co-Authored-By: Claude <noreply@anthropic.com>
The CI runner does not have yarn installed. Switch to npm install
and npm run build. Also add package-lock.json for reproducible
installs and exclude it from the release ZIP.
Co-Authored-By: Claude <noreply@anthropic.com>