#607 fixed

src/App.tsx

@@ -5,11 +5,13 @@ import { createBrowserRouter, RouterProvider } from 'react-router';
 import AppErrorBoundary from './components/common/AppErrorBoundary';
 import { useNavigationTiming } from './hooks/useNavigationTiming';
 import { routes } from './routes';
+import { useRouteChangeLogging } from './hooks/useRouteChangeLogging';
 
 const router = createBrowserRouter(routes);
 
 function App() {
 	useNavigationTiming();
+	useRouteChangeLogging();
 
 	useEffect(() => {
 		const lenis = new Lenis({

src/hooks/useRouteChangeLogging.ts

@@ -0,0 +1,30 @@
+import { useEffect, useRef } from 'react';
+import { useLocation } from 'react-router';
+
+export function useRouteChangeLogging() {
+	const location = useLocation();
+	const previousRoute = useRef<string | null>(null);
+	const lastNavCompletedAt = useRef<number | null>(null);
+	const isFirstNav = useRef(true);
+
+	useEffect(() => {
+		// Vitest sets MODE to 'test' by default; skip logging in that environment.
+		if (import.meta.env.MODE === 'test') return;
+
+		const now = performance.now();
+		const toRoute = location.pathname;
+
+		console.debug('[route-change]', {
+			from_route: isFirstNav.current ? null : previousRoute.current,
+			to_route: toRoute,
+			time_since_last_nav_ms:
+				lastNavCompletedAt.current === null
+					? null
+					: Math.round(now - lastNavCompletedAt.current),
+		});
+
+		isFirstNav.current = false;
+		previousRoute.current = toRoute;
+		lastNavCompletedAt.current = now;
+	}, [location]);
+}