fix: address code review findings

cmd/api/handlers.go

@@ -239,6 +239,30 @@ func RouteSearch(hc *HandlerContext, w http.ResponseWriter, r *http.Request) {
 		}
 	}
 
+	// Detect closed stations by checking if they have real edges in the graph
+	for _, cityID := range []string{req.FromCityID, req.ToCityID} {
+		// Get stations for this city
+		stations := getStationsForCity(cityID)
+		for _, station := range stations {
+			if len(station) > 0 {
+				stationID := station[0]
+				// Check if this station has real edges
+				hasRealEdges := false
+				for _, edge := range hc.Router.Edges() {
+					if edge.From.ID == stationID || edge.To.ID == stationID {
+						if edge.Kind == routing.EdgeKindReal {
+							hasRealEdges = true
+							break
+						}
+					}
+				}
+				if !hasRealEdges {
+					closedStationsMap[stationID] = true
+				}
+			}
+		}
+	}
+
 	// Run Pareto-optimal route search using the graph
 	results := hc.Router.FindRoutesPareto(req.FromCityID, req.ToCityID, opts, closedStationsMap, neighborsMap)