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/unist-util-modify-children/index.d.ts

@@ -0,0 +1,5 @@
+export {modifyChildren} from './lib/index.js'
+export type Modifier<Kind extends import('unist').Parent> =
+  import('./lib/index.js').Modifier<Kind>
+export type Modify<Kind extends import('unist').Parent> =
+  import('./lib/index.js').Modify<Kind>