feat(mall): address book wave 7 frontend, contract, and archive

Live addresses domain for the mall: shared contract (AddressBookEntry +
five client methods), mock adapter state v3, live domain pick, addresses
page CRUD, checkout saved-address picker with manual fallback, demo seed,
and the archived change plus address-book capability spec.

apps/mall/locales/checkout.ts

@@ -15,6 +15,8 @@ export default {
       backToCart: "Back to cart",
       loadError: "Unable to load the order.",
       submitError: "Unable to place the order.",
+      addressRequired: "Please select or fill in a shipping address.",
+      noSavedAddress: "No saved address. Please enter one below.",
       paymentTitle: "Choose payment",
       balance: "Balance payment",
       wechat: "WeChat Pay",
@@ -48,6 +50,8 @@ export default {
       backToCart: "返回购物车",
       loadError: "订单信息加载失败，请稍后重试。",
       submitError: "订单提交失败，请稍后重试。",
+      addressRequired: "请选择或填写收货地址。",
+      noSavedAddress: "暂无收货地址，请在下方填写。",
       paymentTitle: "选择支付方式",
       balance: "余额支付",
       wechat: "微信支付",

apps/mall/locales/user.ts

@@ -68,6 +68,8 @@ export default {
       defaultAddress: "Default",
       setDefault: "Set as default",
       saveAddress: "Save address",
+      country: "Country",
+      saveFailed: "Save failed. Please try again.",
       noAddresses: "No shipping addresses yet.",
       favoritesTitle: "Favorites",
       favoriteProductsTab: "Products",
@@ -159,6 +161,8 @@ export default {
       defaultAddress: "默认",
       setDefault: "设为默认",
       saveAddress: "保存地址",
+      country: "国家",
+      saveFailed: "保存失败，请重试。",
       noAddresses: "暂无收货地址。",
       favoritesTitle: "我的收藏",
       favoriteProductsTab: "商品",