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/zod-to-json-schema/dist/esm/parsers/undefined.js

@@ -0,0 +1,6 @@
+import { parseAnyDef } from "./any.js";
+export function parseUndefinedDef(refs) {
+    return {
+        not: parseAnyDef(refs),
+    };
+}