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/mdast-util-to-markdown/lib/handle/text.js

@@ -0,0 +1,15 @@
+/**
+ * @import {Info, State} from 'mdast-util-to-markdown'
+ * @import {Parents, Text} from 'mdast'
+ */
+
+/**
+ * @param {Text} node
+ * @param {Parents | undefined} _
+ * @param {State} state
+ * @param {Info} info
+ * @returns {string}
+ */
+export function text(node, _, state, info) {
+  return state.safe(node.value, info)
+}