Remove 'Distance only applies to Cheapest' explainer

Closest mode now shows the disabled distance picker with no caption;
the N-stations-within caption still appears in Cheapest mode.

FuelBoard/StationsView.swift

@@ -75,11 +75,7 @@ struct StationsView: View {
                         FuelStore.saveStationLimit(newValue)
                     }
                     .padding(.vertical, 2)
-                    if sortMode == .closest {
+                    if sortMode != .closest {
-                        Text("Distance only applies to Cheapest")
-                            .font(.caption2)
-                            .foregroundStyle(.secondary)
-                    } else {
                         Text("\(totalCount) stations within \(stationLimit) \(distanceUnit.label)")
                             .font(.caption2)
                             .foregroundStyle(.secondary)