Use "node --run" instead of "npm run" (#3764)

This has the advantage that the package manager is no longer involved
after the installation process.

However, previous start commands such as `npm run start` continue to
work. So we don't even have to adapt the documentation.

.gitignore

@@ -84,3 +84,7 @@ Temporary Items
 
 # Ignore positions file (#3518)
 js/positions.js
+
+# Ignore lock files other than package-lock.json
+pnpm-lock.yaml
+yarn.lock