fix(frontend): align API route paths with backend (alerts, price-history)

Change frontend to call /alerts (was /price-alerts) and /products/{id}/prices
(was /products/{id}/price-history) to match the backend router mounts.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

src/test/mocks/handlers.ts

@@ -61,5 +61,5 @@ export const handlers = [
   http.get('/api/v1/products', () => HttpResponse.json(mockProducts)),
   http.get('/api/v1/products/prod_1', () => HttpResponse.json(mockProducts[0])),
   http.get('/api/v1/coupons', () => HttpResponse.json(mockCoupons)),
-  http.get('/api/v1/price-alerts', () => HttpResponse.json(mockAlerts)),
+  http.get('/api/v1/alerts', () => HttpResponse.json(mockAlerts)),
 ]