Now I understand the full requirements. This is a barbershop scheduling system with client booking and admin dashboard. Since the user declined database integration, I'll build a fully functional UI with in-memory/localStorage-based state management. Let me plan and build this systematically.

Let me check the existing UI components available:

Good, I have all the shadcn components available. Now let me build the entire system. I'll start with the theme, shared types/store, and then build all pages.

Now let me create the shared types and store:

Now let me create the manifest.json and the main page:

Now let me move to task 2 and build the client booking page:

Now let me create the main page:

Now let me move to the admin dashboard:

Now let me move to the final task and create the admin page with authentication:

The barbershop scheduling system is now complete. Here's what was built:

Client side (/) -- A landing page with a "Agendar agora" button that leads to a multi-step booking flow: choose a service, pick a date from the interactive calendar, select an available time slot, then fill in name and phone to confirm. The calendar respects business hours (Tue-Sat 08-18h, Sun 08-12h), automatically blocks the first Sunday of each month, and prevents double-bookings.

Admin dashboard (/admin) -- A login-protected panel (credentials: admin / admin123) with 5 tabs accessible via a mobile-friendly bottom navigation: Overview (today/week/month stats + revenue), Agenda (day/week/month views with cancel capability), Services (CRUD for services with pricing), Blocked slots (block full days or specific hours for holidays/breaks), and Settings (configure open/close times per weekday). All data persists via localStorage since no database integration was added -- you can connect a database later for production use.