feat: add high-converting 404 page with bestsellers, testimonials, and urgency messages

- Create conversion-optimized 404 page with multiple sections
- Add NotFound translations for en, sr, de, fr locales
- Implement rotating urgency messages component
- Display first 4 products as bestsellers with product cards
- Show 6 rotating testimonials from ProductReviews
- Include TrustBadges for social proof
- Add OpenPanel tracking for 404 page views
- Final CTA section with link to all products

SEO: Returns proper 404 status while converting lost traffic into customers

src/i18n/messages/de.json

@@ -384,5 +384,20 @@
     "orderNumber": "Bestellnummer",
     "confirmationEmail": "Sie erhalten in Kürze eine Bestätigungs-E-Mail. Wir werden Sie kontaktieren, um Nachnahme zu arrangieren.",
     "continueShoppingBtn": "Weiter einkaufen"
+  },
+  "NotFound": {
+    "title": "Wir konnten diese Seite nicht finden...",
+    "subtitle": "...aber wir haben etwas Besseres für Sie gefunden",
+    "shopBestsellers": "Bestseller Shoppen",
+    "bestsellersTitle": "Unsere Bestseller Shoppen",
+    "testimonialsTitle": "Schließen Sie sich 50.000+ zufriedenen Kunden an",
+    "finalCTATitle": "Bereit, Ihre Reise zu beginnen?",
+    "finalCTASubtitle": "Entdecken Sie den natürlichen Unterschied",
+    "viewAllProducts": "Alle Produkte Shoppen",
+    "urgency1": "🔥 500+ Menschen kaufen gerade unsere Bestseller",
+    "urgency2": "⚡ Nur noch 50 Flaschen unseres beliebtesten Serums",
+    "urgency3": "📦 Kostenloser Versand bei Bestellungen über {amount}",
+    "urgency4": "⭐ 4,9/5 Bewertung von 50.000+ zufriedenen Kunden",
+    "urgency5": "🚀 Bestellungen werden innerhalb von 24 Stunden versandt"
   }
 }

src/i18n/messages/en.json

@@ -431,5 +431,20 @@
     "orderNumber": "Order Number",
     "confirmationEmail": "You will receive a confirmation email shortly. We will contact you to arrange Cash on Delivery.",
     "continueShoppingBtn": "Continue Shopping"
+  },
+  "NotFound": {
+    "title": "We couldn't find that page...",
+    "subtitle": "...but we found something better for you",
+    "shopBestsellers": "Shop Bestsellers",
+    "bestsellersTitle": "Shop Our Bestsellers",
+    "testimonialsTitle": "Join 50,000+ Happy Customers",
+    "finalCTATitle": "Ready to Start Your Journey?",
+    "finalCTASubtitle": "Discover the natural difference",
+    "viewAllProducts": "Shop All Products",
+    "urgency1": "🔥 500+ people are shopping our bestsellers right now",
+    "urgency2": "⚡ Only 50 bottles left of our most popular serum",
+    "urgency3": "📦 Free shipping on orders over {amount}",
+    "urgency4": "⭐ 4.9/5 rating from 50,000+ happy customers",
+    "urgency5": "🚀 Orders ship within 24 hours"
   }
 }

src/i18n/messages/fr.json

@@ -384,5 +384,20 @@
     "orderNumber": "Numéro de Commande",
     "confirmationEmail": "Vous recevrez bientôt un email de confirmation. Nous vous contacterons pour organiser le paiement contre-remboursement.",
     "continueShoppingBtn": "Continuer les Achats"
+  },
+  "NotFound": {
+    "title": "Nous n'avons pas trouvé cette page...",
+    "subtitle": "...mais nous avons trouvé quelque chose de mieux pour vous",
+    "shopBestsellers": "Acheter les Best-sellers",
+    "bestsellersTitle": "Acheter Nos Best-sellers",
+    "testimonialsTitle": "Rejoignez 50 000+ Clients Satisfaits",
+    "finalCTATitle": "Prêt à Commencer Votre Voyage?",
+    "finalCTASubtitle": "Découvrez la différence naturelle",
+    "viewAllProducts": "Voir Tous les Produits",
+    "urgency1": "🔥 500+ personnes achètent nos best-sellers en ce moment",
+    "urgency2": "⚡ Plus que 50 bouteilles de notre sérum le plus populaire",
+    "urgency3": "📦 Livraison gratuite pour les commandes supérieures à {amount}",
+    "urgency4": "⭐ Note de 4,9/5 de 50 000+ clients satisfaits",
+    "urgency5": "🚀 Les commandes sont expédiées sous 24 heures"
   }
 }

src/i18n/messages/sr.json

@@ -430,5 +430,20 @@
     "orderNumber": "Broj narudžbine",
     "confirmationEmail": "Uскoro ćete primiti email potvrde. Kontaktiraćemo vas da dogovorimo pouzećem plaćanje.",
     "continueShoppingBtn": "Nastavi kupovinu"
+  },
+  "NotFound": {
+    "title": "Nismo mogli da pronađemo tu stranicu...",
+    "subtitle": "...ali smo pronašli nešto bolje za vas",
+    "shopBestsellers": "Kupi Najprodavanije",
+    "bestsellersTitle": "Kupi Naše Najprodavanije Proizvode",
+    "testimonialsTitle": "Pridruži se 50,000+ Zadovoljnih Kupaca",
+    "finalCTATitle": "Spremni da Zapocnete Svoje Putovanje?",
+    "finalCTASubtitle": "Otkrijte prirodnu razliku",
+    "viewAllProducts": "Pogledaj Sve Proizvode",
+    "urgency1": "🔥 500+ ljudi kupuje naše najprodavanije proizvode upravo sada",
+    "urgency2": "⚡ Preostalo samo 50 bočica našeg najpopularnijeg seruma",
+    "urgency3": "📦 Besplatna dostava za porudžbine preko {amount} RSD",
+    "urgency4": "⭐ Ocena 4.9/5 od 50,000+ zadovoljnih kupaca",
+    "urgency5": "🚀 Porudžbine se šalju u roku od 24 sata"
   }
 }