More fixes

frontend/src/hooks/useTravelTime.ts

@@ -1,4 +1,6 @@
 import { useState, useCallback, useMemo } from 'react';
+import type { ComponentType } from 'react';
+import { CarIcon, BicycleIcon, WalkingIcon, TransitIcon } from '../components/ui/icons';
 
 export type TransportMode = 'car' | 'bicycle' | 'walking' | 'transit';
 
@@ -18,6 +20,13 @@ export const MODE_DESCRIPTIONS: Record<TransportMode, string> = {
   transit: 'Journey time by train, tube, and bus',
 };
 
+export const MODE_ICONS: Record<TransportMode, ComponentType<{ className?: string }>> = {
+  car: CarIcon,
+  bicycle: BicycleIcon,
+  walking: WalkingIcon,
+  transit: TransitIcon,
+};
+
 export interface TravelTimeEntry {
   mode: TransportMode;
   slug: string;