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/space-separated-tokens/index.js

@@ -0,0 +1,24 @@
+/**
+ * Parse space-separated tokens to an array of strings.
+ *
+ * @param {string} value
+ *   Space-separated tokens.
+ * @returns {Array<string>}
+ *   List of tokens.
+ */
+export function parse(value) {
+  const input = String(value || '').trim()
+  return input ? input.split(/[ \t\n\r\f]+/g) : []
+}
+
+/**
+ * Serialize an array of strings as space separated-tokens.
+ *
+ * @param {Array<string|number>} values
+ *   List of tokens.
+ * @returns {string}
+ *   Space-separated tokens.
+ */
+export function stringify(values) {
+  return values.join(' ').trim()
+}