Add guest review page + switch to 5-star rating system

- New public page /review/:slug — guest-facing review form with 5-star selector, optional comment, positive flow (redirect buttons to platforms), negative flow (thank you message)
- Switch all rating scales from 10-point to 5-star in ReviewsPage: mock data, StarRating component, avgRating sub-label, NPS thresholds, threshold slider (1–4), settings cards
- Rating badge in review list now shows number + star icon
- Register route in App.tsx as public (no auth required)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/App.tsx

@@ -34,6 +34,7 @@ import { DynamicPricingPage } from './pages/DynamicPricingPage'
 import { LoyaltyPage } from './pages/LoyaltyPage'
 import { MaintenancePage } from './pages/MaintenancePage'
 import { DiscountsPage } from './pages/DiscountsPage'
+import { GuestReviewPage } from './pages/GuestReviewPage'
 
 export default function App() {
   return (
@@ -46,6 +47,7 @@ export default function App() {
             <Routes>
               {/* Public */}
               <Route path="/login" element={<LoginPage />} />
+              <Route path="/review/:slug" element={<GuestReviewPage />} />
 
               {/* App routes */}
               <Route element={<AppLayout />}>