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/rehype-stringify/lib/index.js

@@ -0,0 +1,31 @@
+/**
+ * @import {Root} from 'hast'
+ * @import {Options} from 'hast-util-to-html'
+ * @import {Compiler, Processor} from 'unified'
+ */
+
+import {toHtml} from 'hast-util-to-html'
+
+/**
+ * Plugin to add support for serializing as HTML.
+ *
+ * @param {Options | null | undefined} [options]
+ *   Configuration (optional).
+ * @returns {undefined}
+ *   Nothing.
+ */
+export default function rehypeStringify(options) {
+  /** @type {Processor<undefined, undefined, undefined, Root, string>} */
+  // @ts-expect-error: TS in JSDoc generates wrong types if `this` is typed regularly.
+  const self = this
+  const settings = {...self.data('settings'), ...options}
+
+  self.compiler = compiler
+
+  /**
+   * @type {Compiler<Root, string>}
+   */
+  function compiler(tree) {
+    return toHtml(tree, settings)
+  }
+}