docs: change example query to Solve this integral

README.md

@@ -65,7 +65,7 @@ sys.path.insert(0, path)
 from router import R2Router
 
 router = R2Router.from_pretrained(path, embed_url="http://localhost:8000")
-result = router.route_text("What is the capital of France?")
+result = router.route_text("Solve this integral")
 print(f"Model: {result['model_full_name']}, Budget: {result['token_limit']}")
 print(f"Estimated Quality: {result['predicted_quality']:.3f}, Estimated Cost: ${result['predicted_cost']:.6f}")
 ```