feat: implement locale-aware routing with [locale] dynamic segments

WARNING: This change breaks existing SEO URLs for Serbian locale.

Changes:
- Migrated from separate locale folders (src/app/en/, src/app/de/, etc.)
  to [locale] dynamic segments (src/app/[locale]/)
- Serbian is now at /sr/ instead of / (root)
- English at /en/, German at /de/, French at /fr/
- All components updated to generate locale-aware links
- Root / now redirects to /sr (307 temporary redirect)

SEO Impact:
- Previously indexed Serbian URLs (/, /products, /about, /contact)
  will now return 404 or redirect to /sr/* URLs
- This is a breaking change for SEO - Serbian pages should ideally
  remain at root (/) with only non-default locales getting prefix
- Consider implementing 301 redirects from old URLs to maintain
  search engine rankings

Technical Notes:
- next-intl v4 with [locale] structure requires ALL locales to
  have the prefix (cannot have default locale at root)
- Alternative approach would be separate folder structure per locale

src/components/home/NewHero.tsx

@@ -4,6 +4,7 @@ import { motion } from "framer-motion";
 import { Star, ShoppingBag } from "lucide-react";
 import Image from "next/image";
 import Link from "next/link";
+import { useLocale } from "next-intl";
 import { useSaleorCheckoutStore } from "@/stores/saleorCheckoutStore";
 import type { Product } from "@/types/saleor";
 import { getProductPrice, getProductImage, formatPrice, parseDescription } from "@/lib/saleor";
@@ -13,6 +14,7 @@ interface NewHeroProps {
 }
 
 export default function NewHero({ featuredProduct }: NewHeroProps) {
+  const locale = useLocale();
   const { addLine, openCart } = useSaleorCheckoutStore();
 
   const handleAddToCart = async () => {
@@ -150,13 +152,13 @@ export default function NewHero({ featuredProduct }: NewHeroProps) {
 
           <div className="flex gap-4 justify-end">
             <Link
-              href="/products"
+              href={`/${locale}/products`}
               className="inline-block bg-[#1A1A1A] text-white px-8 py-4 text-sm tracking-wide hover:bg-[#1A1A1A]/90 transition-colors"
             >
               Shop Collection
             </Link>
             <Link
-              href="/about"
+              href={`/${locale}/about`}
               className="inline-block border border-[#1A1A1A] text-[#1A1A1A] px-8 py-4 text-sm tracking-wide hover:bg-[#1A1A1A] hover:text-white transition-colors"
             >
               Our Story
@@ -168,7 +170,7 @@ export default function NewHero({ featuredProduct }: NewHeroProps) {
       {/* Mobile CTA */}
       <div className="lg:hidden relative z-10 px-6 pb-12">
         <Link
-          href="/products"
+          href={`/${locale}/products`}
           className="block w-full bg-[#1A1A1A] text-white text-center py-4 text-sm tracking-wide"
         >
           Shop Now