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/root.js

@@ -0,0 +1,23 @@
+/**
+ * @import {Info, State} from 'mdast-util-to-markdown'
+ * @import {Parents, Root} from 'mdast'
+ */
+
+import {phrasing} from 'mdast-util-phrasing'
+
+/**
+ * @param {Root} node
+ * @param {Parents | undefined} _
+ * @param {State} state
+ * @param {Info} info
+ * @returns {string}
+ */
+export function root(node, _, state, info) {
+  // Note: `html` nodes are ambiguous.
+  const hasPhrasing = node.children.some(function (d) {
+    return phrasing(d)
+  })
+
+  const container = hasPhrasing ? state.containerPhrasing : state.containerFlow
+  return container.call(state, node, info)
+}