feat(F-006): users profile, addresses and RBAC

- users module: profile + address CRUD behind use cases (users_profiles,
  users_addresses)
- roles customer/admin on identity_users; role resolved from DB per request
- shared auth contract (Authenticate, requireRole, requireOwnerOrAdmin)
  injected from composition root; users never imports identity
- authorization runs before existence checks; address SQL scoped by user_id
- @fastify/cookie registered once at app root (cross-module)
- migrations 003_identity_roles + 004_users (reversible)
- no new npm dependencies; tests: unit 52, integration 22

Gates: reviewer/security/qa APPROVED; verify.sh green

project/migrations/003_identity_roles.js

@@ -0,0 +1,19 @@
+/**
+ * Identity schema evolution: roles for RBAC (introduced by F-006).
+ * Role is authorization truth and belongs with the account row.
+ * Shipped as its own migration to keep ownership explicit.
+ */
+
+/** @param {import('node-pg-migrate').MigrationBuilder} pgm */
+export const up = (pgm) => {
+  pgm.sql(`
+    ALTER TABLE identity_users
+      ADD COLUMN role text NOT NULL DEFAULT 'customer'
+      CHECK (role IN ('customer', 'admin'))
+  `);
+};
+
+/** @param {import('node-pg-migrate').MigrationBuilder} pgm */
+export const down = (pgm) => {
+  pgm.sql('ALTER TABLE identity_users DROP COLUMN role');
+};