Add Windows PowerShell alternative for running E2E tests in README and
update smoke tests to verify the target is a Shaarli instance, with
better diagnostics for misconfigured URLs.
Introduce a Node build system for minified CSS/JS with content hashes,
add PWA support, i18n helpers, accessibility improvements, and more
translatable strings. Move theme configuration from bookmarks to
localStorage, add Playwright tests, and set up CI workflows.
bruno