fix: address code review findings

internal/metrics/metrics.go

@@ -28,7 +28,6 @@ type Metrics struct {
 
 // histogram tracks duration values and computes simple stats.
 type histogram struct {
-	mu        sync.Mutex
 	values    []int64 // nanoseconds
 	maxValues int
 }

internal/routing/graph.go

@@ -915,7 +915,7 @@ type SearchResult struct {
 // route in all three metrics simultaneously. Routes are sorted according to the RankingMode
 // in SearchOptions: "fastest" (default, by duration), "fewest_transfers" (by transfers),
 // or "cheapest" (by cost).
-func (g *Graph) FindRoutesPareto(originID, destID string, opts SearchOptions, closedStations map[string]bool, neighbors map[string][]storage.StationNeighbor) []*Itinerary {
+func (g *Graph) FindRoutesPareto(originID, destID string, opts SearchOptions, closedStations map[string]bool, neighbors map[string][]storage.StationNeighbor, yclient ...*yandex.Client) []*Itinerary {
 	// Run multiple searches with different strategies to find diverse routes
 	var allItineraries []*Itinerary
 
@@ -925,7 +925,7 @@ func (g *Graph) FindRoutesPareto(originID, destID string, opts SearchOptions, cl
 		optsCopy := opts
 		optsCopy.MaxTransfers = 5
 
-		result := g.FindRoute(originID, destID, optsCopy, closedStations, neighbors)
+		result := g.FindRoute(originID, destID, optsCopy, closedStations, neighbors, yclient...)
 		if result != nil && result.TotalDuration > 0 {
 			allItineraries = append(allItineraries, result)
 		}
@@ -934,7 +934,7 @@ func (g *Graph) FindRoutesPareto(originID, destID string, opts SearchOptions, cl
 			optsCopy := opts
 			optsCopy.MaxTransfers = maxTransfers
 
-			result := g.FindRoute(originID, destID, optsCopy, closedStations, neighbors)
+			result := g.FindRoute(originID, destID, optsCopy, closedStations, neighbors, yclient...)
 			if result != nil && result.TotalDuration > 0 {
 				allItineraries = append(allItineraries, result)
 			}

static/app.js

@@ -241,8 +241,8 @@ async function searchRoutes(formData) {
                 'Content-Type': 'application/json'
             },
             body: JSON.stringify({
-                from: formData.get('from'),
-                to: formData.get('to'),
+                from_city_id: formData.get('from'),
+                to_city_id: formData.get('to'),
                 date: formData.get('date')
             })
         });