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/@astrojs/prism/Prism.astro

@@ -0,0 +1,17 @@
+---
+import { runHighlighterWithAstro } from './dist/highlighter';
+
+interface Props {
+	class?: string;
+	lang?: string;
+	code: string;
+}
+
+const { class: className, lang, code } = Astro.props as Props;
+const { classLanguage, html } = runHighlighterWithAstro(lang, code);
+---
+
+<pre
+	class={[className, classLanguage]
+		.filter(Boolean)
+		.join(' ')}><code class={classLanguage} set:html={html} /></pre>