feat: implement multiple saved addresses with modal selector in checkout

- Add AddressController with full CRUD API for saved addresses
- Implement address management UI in My Account > Addresses
- Add modal-based address selector in checkout (Tokopedia-style)
- Hide checkout forms when saved address is selected
- Add search functionality in address modal
- Auto-select default addresses on page load
- Fix variable products to show 'Select Options' instead of 'Add to Cart'
- Add admin toggle for multiple addresses feature
- Clean up debug logs and fix TypeScript errors

customer-spa/src/components/Layout/Footer.tsx

@@ -138,7 +138,7 @@ export default function Footer() {
                   />
                   <button
                     type="submit"
-                    className="absolute right-1.5 top-1.5 p-1.5 bg-gray-900 text-white rounded-md hover:bg-gray-800 transition-colors"
+                    className="font-[inherit] absolute right-1.5 top-1.5 p-1.5 bg-gray-900 text-white rounded-md hover:bg-gray-800 transition-colors"
                   >
                     <Mail className="h-4 w-4" />
                   </button>