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/vfile/lib/minurl.shared.js

@@ -0,0 +1,31 @@
+/**
+ * Checks if a value has the shape of a WHATWG URL object.
+ *
+ * Using a symbol or instanceof would not be able to recognize URL objects
+ * coming from other implementations (e.g. in Electron), so instead we are
+ * checking some well known properties for a lack of a better test.
+ *
+ * We use `href` and `protocol` as they are the only properties that are
+ * easy to retrieve and calculate due to the lazy nature of the getters.
+ *
+ * We check for auth attribute to distinguish legacy url instance with
+ * WHATWG URL instance.
+ *
+ * @param {unknown} fileUrlOrPath
+ *   File path or URL.
+ * @returns {fileUrlOrPath is URL}
+ *   Whether it’s a URL.
+ */
+// From: <https://github.com/nodejs/node/blob/6a3403c/lib/internal/url.js#L720>
+export function isUrl(fileUrlOrPath) {
+  return Boolean(
+    fileUrlOrPath !== null &&
+      typeof fileUrlOrPath === 'object' &&
+      'href' in fileUrlOrPath &&
+      fileUrlOrPath.href &&
+      'protocol' in fileUrlOrPath &&
+      fileUrlOrPath.protocol &&
+      // @ts-expect-error: indexing is fine.
+      fileUrlOrPath.auth === undefined
+  )
+}