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/micromark-extension-gfm-task-list-item/lib/html.d.ts

@@ -0,0 +1,13 @@
+/**
+ * @import {HtmlExtension} from 'micromark-util-types'
+ */
+/**
+ * Create an HTML extension for `micromark` to support GFM task list items when
+ * serializing to HTML.
+ *
+ * @returns {HtmlExtension}
+ *   Extension for `micromark` that can be passed in `htmlExtensions` to
+ *   support GFM task list items when serializing to HTML.
+ */
+export function gfmTaskListItemHtml(): HtmlExtension;
+import type { HtmlExtension } from 'micromark-util-types';