frontend phase 0: app shells, design system & data/contract patterns

Turn the starter into the Balinyaar foundation for the three actor
experiences and lock in the patterns later phases copy.

- Cleanup: remove toastDemo namespace, placeholder home page, and the two
  dead icons; fix BottomBar to use usePathname (locale-aware active tab).
- Three actor shells under (private-routes), no layout above [locale]:
  customer (customer) group with the 5-tab bottom nav; nurse (/nurse) and
  admin (/admin) on the shared sidebar engine. Role model via constants/roles
  + useActorRole (defaults to customer until roles land in f1-b2).
- services/{domain} reference (patients) with a mock behind a config seam,
  hierarchical query keys, deliberate staleTime, and mutation invalidation;
  shared ApiEnvelope/Paginated wire types + unwrap() in lib/api/types.
- Money (integer-safe IRR/Toman) + Shamsi-date utils; toEnglishDigits helper.
- Shared composites, each tested: OtpInput, PhoneNumberField, StepperHeader,
  StatusChip, PlaceholderScreen.
- i18n: seed nav/common/shell/patients in both locales; document namespace
  conventions. Update client/CLAUDE.md Project Structure + fix ColorSchemeScript
  doc drift. Add phase report, STATUS, and REQ-001 (envelope/casing/pagination).

Gate: npm run check + test:ci green (72 tests); build green with NEXT_PUBLIC_API_URL.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

client/src/constants/roles.ts

@@ -0,0 +1,15 @@
+/**
+ * The three Balinyaar actor experiences. Each maps to a route-group shell under
+ * `(private-routes)` and its own navigation. The real role list arrives with the
+ * server in f1-b2; until then `useActorRole()` defaults to CUSTOMER so the shells
+ * render gracefully without a role on the session.
+ */
+export const APP_ROLES = {
+  CUSTOMER: 'customer',
+  NURSE: 'nurse',
+  ADMIN: 'admin',
+} as const;
+
+export type AppRole = (typeof APP_ROLES)[keyof typeof APP_ROLES];
+
+export const DEFAULT_ROLE: AppRole = APP_ROLES.CUSTOMER;