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/astro/dist/cli/infra/process-operating-system-provider.js

@@ -0,0 +1,12 @@
+class ProcessOperatingSystemProvider {
+  #platformToOs = {
+    darwin: "macOS",
+    win32: "Windows",
+    linux: "Linux"
+  };
+  name = process.platform;
+  displayName = `${this.#platformToOs[this.name] ?? this.name} (${process.arch})`;
+}
+export {
+  ProcessOperatingSystemProvider
+};