Feature: Client foundation — Zustand, daisyUI, and app shell

[FadyGergesRezk]

Replace the placeholder app shell with a production-ready layout and install the shared dependencies all feature pages will build on.

Stack to install

• TanStack Query v5 — server state, caching, mutations
• Zustand — UI-only state (selected row, modal open/close, active tab); not for server data
• React Hook Form + Zod — form handling and validation tied to OpenAPI-generated types
• daisyUI — pre-built Tailwind component library with complete design system (colors, typography, themes)

Tasks

• Install and configure TanStack Query v5; wrap app in QueryClientProvider with sensible defaults (staleTime, gcTime, no retry on 401/403)
• Install Zustand; create a shared store scaffold under src/store/ for UI-only state
• Install React Hook Form and Zod; add src/lib/forms.ts as a shared entry point for zodResolver
• Install daisyUI and configure Tailwind v4 theme with daisyUI preset
• Configure Axios interceptors on the shared client: attach Authorization: Bearer <token> header on requests; redirect to /login on 401, surface 403 as a toast
• Replace the inline header in AppRouter.tsx with a proper layout component (src/app/layout/) with sidebar or top nav using daisyUI components
• Add a shared ErrorMessage and LoadingSpinner component to src/components/ui/ using daisyUI primitives
• Remove ServicePlaceholderPage and hello-endpoint imports; replace each route with an empty page stub in its feature folder
• Wire up React Router v7 loaders pattern so each route can prefetch via queryClient.ensureQueryData()

Acceptance criteria

• pnpm build passes with no type errors
• App loads with the new layout; all 6 nav links navigate to their stub pages
• QueryClientProvider wraps the app; TanStack Query DevTools visible in dev
• Zustand store is importable; daisyUI components are available for feature issues
• Axios interceptor attaches the Bearer token on every request