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/get-east-asian-width/index.js

@@ -0,0 +1,30 @@
+import {getCategory, isAmbiguous, isFullWidth, isWide} from './lookup.js';
+
+function validate(codePoint) {
+	if (!Number.isSafeInteger(codePoint)) {
+		throw new TypeError(`Expected a code point, got \`${typeof codePoint}\`.`);
+	}
+}
+
+export function eastAsianWidthType(codePoint) {
+	validate(codePoint);
+
+	return getCategory(codePoint);
+}
+
+export function eastAsianWidth(codePoint, {ambiguousAsWide = false} = {}) {
+	validate(codePoint);
+
+	if (
+		isFullWidth(codePoint)
+		|| isWide(codePoint)
+		|| (ambiguousAsWide && isAmbiguous(codePoint))
+	) {
+		return 2;
+	}
+
+	return 1;
+}
+
+// Private exports for https://github.com/sindresorhus/is-fullwidth-code-point
+export {isFullWidth as _isFullWidth, isWide as _isWide} from './lookup.js';