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/dset/dist/index.mjs

@@ -0,0 +1,9 @@
+export function dset(obj, keys, val) {
+	keys.split && (keys=keys.split('.'));
+	var i=0, l=keys.length, t=obj, x, k;
+	while (i < l) {
+		k = ''+keys[i++];
+		if (k === '__proto__' || k === 'constructor' || k === 'prototype') break;
+		t = t[k] = (i === l) ? val : (typeof(x=t[k])===typeof(keys)) ? x : (keys[i]*0 !== 0 || !!~(''+keys[i]).indexOf('.')) ? {} : [];
+	}
+}