fix: Fix product page syntax errors

1. Remove duplicate/broken code in product tables section
2. Fix PostCSS config for Tailwind 4
3. Add @tailwindcss/postcss dependency
4. Remove --production flag from Dockerfile (sharp required)

All fixes enable successful Docker build with favicon working.

node_modules/astro/dist/assets/utils/url.js

@@ -0,0 +1,11 @@
+const PLACEHOLDER_BASE = "astro://placeholder";
+function createPlaceholderURL(pathOrUrl) {
+  return new URL(pathOrUrl, PLACEHOLDER_BASE);
+}
+function stringifyPlaceholderURL(url) {
+  return url.href.replace(PLACEHOLDER_BASE, "");
+}
+export {
+  createPlaceholderURL,
+  stringifyPlaceholderURL
+};