Added ShippingSelector component that:
- Displays country selection dropdown
- Fetches available Royal Mail shipping quotes based on cart weight
- Shows delivery estimates and international delivery warnings
- Lets customers select preferred shipping service
- Auto-selects cheapest option by default
Integrated into checkout:
- Shows shipping selector in both logged-in and guest flows
- Displays shipping cost breakdown in order summary
- Passes shipping country and service to checkout API
- Validates shipping selection before processing payment
Andymick
5538938020