feat: add 30-day money back guarantee trust badge above complete order button

- Add green trust badge with checkmark icon above 'Complete Order' button
- Add translations for all locales (EN, SR, DE, FR)
- Badge includes: '30-Day Money-Back Guarantee' text
- Styled with green background and border to match trust/conversion theme

src/i18n/messages/de.json

@@ -361,6 +361,7 @@
     "cashOnDeliveryDesc": "Bezahlen Sie, wenn Ihre Bestellung an Ihre Tür geliefert wird.",
     "processing": "Wird bearbeitet...",
     "completeOrder": "Bestellung abschließen - {total}",
+    "moneyBackGuarantee": "30 Tage Geld-zurück-Garantie",
     "orderSummary": "Bestellübersicht",
     "qty": "Menge",
     "subtotal": "Zwischensumme",

src/i18n/messages/en.json

@@ -407,6 +407,7 @@
     "cashOnDeliveryDesc": "Pay when your order is delivered to your door.",
     "processing": "Processing...",
     "completeOrder": "Complete Order - {total}",
+    "moneyBackGuarantee": "30-Day Money-Back Guarantee",
     "orderSummary": "Order Summary",
     "qty": "Qty",
     "subtotal": "Subtotal",

src/i18n/messages/fr.json

@@ -361,6 +361,7 @@
     "cashOnDeliveryDesc": "Payez lorsque votre commande est livrée à votre porte.",
     "processing": "En cours...",
     "completeOrder": "Finaliser la Commande - {total}",
+    "moneyBackGuarantee": "Garantie de remboursement de 30 jours",
     "orderSummary": "Résumé de la Commande",
     "qty": "Qté",
     "subtotal": "Sous-total",

src/i18n/messages/sr.json

@@ -407,6 +407,7 @@
     "cashOnDeliveryDesc": "Platite kada vam narudžbina bude isporučena na vrata.",
     "processing": "Obrađivanje...",
     "completeOrder": "Završi narudžbinu - {total}",
+    "moneyBackGuarantee": "30-dnevna garancija povrata novca",
     "orderSummary": "Pregled narudžbine",
     "qty": "Kol",
     "subtotal": "Ukupno",