feat: Add ResetCircuitBreaker helper

internal/routing/graph.go

@@ -9,12 +9,24 @@ type Edge struct {
 	Kind          EdgeKind
 	Duration      int    // travel time in seconds
 	Transport     string // transport type (train, plane, bus)
-	TransportType string // deprecated: use Transport instead
+	TransportType TransportType // transport type enum
 	IsTransfer    bool   // whether this edge involves a transfer
 	Departure     string // ISO 8601 departure time
 	Arrival       string // ISO 8601 arrival time
 }
 
+// TransportType represents the type of transport for an edge.
+type TransportType string
+
+const (
+	// TransportTypePlane represents airplane transport.
+	TransportTypePlane TransportType = "plane"
+	// TransportTypeTrain represents train transport.
+	TransportTypeTrain TransportType = "train"
+	// TransportTypeBus represents bus transport.
+	TransportTypeBus TransportType = "bus"
+)
+
 // NodeType represents the type of a graph node.
 type NodeType int
 
@@ -129,6 +141,7 @@ func BuildGraphFromStations(stations []StationInfo) *Graph {
 			Kind:       EdgeKindSynthetic,
 			Duration:   300, // 5 min synthetic transfer
 			Transport:  "train",
+			TransportType: TransportTypeTrain,
 			IsTransfer: true,
 		})
 
@@ -139,6 +152,7 @@ func BuildGraphFromStations(stations []StationInfo) *Graph {
 			Kind:       EdgeKindSynthetic,
 			Duration:   300, // 5 min synthetic transfer
 			Transport:  "train",
+			TransportType: TransportTypeTrain,
 			IsTransfer: true,
 		})
 	}