Next.js standalone output places client chunks under dist/static, but the
generated HTML references /_next/static/... which Nginx serves from
dist/_next/static. Mirror static -> _next/static during build so CSS/JS
load with correct MIME types instead of 404.
Next.js standalone output does not place public/ files at the dist root,
so rsync --delete was removing logo/favicon/fonts/images from production.
Copy public/ into dist after build so Nginx can serve them.