Widget: family-aware row cap — large/extraLarge show 5 stations, medium 3

The 3-row cap was hardcoded for the medium widget height; large widgets
have ~2x the height and fit 5 compact rows. Timeline now carries up to
8 stations (was 4) so the large list never starves. Distance picker
still controls which stations are in range; the visible row count now
depends on widget size, not the distance setting.

FuelBoardWidgets/FuelPriceWidget.swift

@@ -64,7 +64,7 @@ struct FuelPriceTimelineProvider: AppIntentTimelineProvider {
             .filter { $0.prices[.e10] != nil }
             .sorted { $0.prices[.e10]! < $1.prices[.e10]! }
         return FuelPriceEntry(
-            date: Date(), stations: Array(sample.prefix(4)),
+            date: Date(), stations: Array(sample.prefix(8)),
             fuel: .e10, sort: .cheapest, isFavourites: false,
             location: nil, locationSource: "none", unit: unit
         )
@@ -189,7 +189,7 @@ struct FuelPriceTimelineProvider: AppIntentTimelineProvider {
         }
 
         return FuelPriceEntry(
-            date: Date(), stations: Array(ordered.prefix(4)),
+            date: Date(), stations: Array(ordered.prefix(8)),
             fuel: fuel, sort: sort, isFavourites: isFavourites,
             location: location, locationSource: source,
             unit: unit
@@ -287,6 +287,16 @@ struct FuelPriceWidgetView: View {
         .widgetURL(station.widgetDirectionsURL)
     }
 
+    /// How many station rows each family can fit: medium widgets are short
+    /// (158pt) so 3 rows is the safe cap; large/extraLarge have ~2× the height
+    /// and fit 5 compact rows. Small widgets use singleStation instead.
+    private var maxRows: Int {
+        switch family {
+        case .systemMedium: return 3
+        default: return 5
+        }
+    }
+
     private var stationList: some View {
         let cheapest = entry.stations.compactMap { $0.prices[entry.fuel] }.min()
         return VStack(alignment: .leading, spacing: 6) {
@@ -302,7 +312,7 @@ struct FuelPriceWidgetView: View {
                     .font(.caption2)
                     .foregroundStyle(.secondary)
             }
-            ForEach(entry.stations.prefix(3)) { station in
+            ForEach(entry.stations.prefix(maxRows)) { station in
                 Link(destination: station.widgetDirectionsURL ?? URL(string: "maps://")!) {
                     HStack(spacing: 8) {
                         Text(station.name)