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/nuxt.config.ts

@@ -9,7 +9,7 @@ export default defineNuxtConfig({
       // Domains served by the live backend; every other domain stays on the
       // fixed-data adapter. Override with NUXT_PUBLIC_LIVE_DOMAINS='["catalog"]'.
       // See openspec/changes/replace-mock-api-wave-1/design.md and waves 2-3.
-      liveDomains: ["catalog", "currency", "content", "shops", "brands", "auth", "cart", "orders", "shipments", "invoices"],
+      liveDomains: ["catalog", "currency", "content", "shops", "brands", "auth", "cart", "orders", "shipments", "invoices", "addresses"],
       appName: "mall",
     },
   },