Establish frontend type checking

web/src/pages/lvgmc-forecast/CsvMapData.tsx

@@ -63,6 +63,7 @@ export const CsvMapData: Component<{
                 [img, arrowImg],
                 getCityData(),
                 tmpWindData,
+                ['', ''],
                 resolutionProps.map_3840x1440_wind,
             )
         }
@@ -77,4 +78,4 @@ export const CsvMapData: Component<{
             style={{ 'width': '1000px', 'height': '374px' }}
         />
     </>
-}
+}

web/src/pages/map-graphics/MapGraphics.tsx

@@ -34,7 +34,7 @@ export function Faktiska() {
             next[observation.city] = observation.value == null ? "" : observation.value.toString();
         });
         setValues(next);
-        setOverrides(new Set());
+        setOverrides(new Set<FaktiskaStation>());
     });
 
     const observationsByCity = () => new Map((latest() ?? []).map(item => [item.city, item]));