Widget links maps:// directly so CarPlay can route to Apple Maps

- The widget now uses the native maps://?daddr= scheme for taps in both
  sizes. In CarPlay there is no containing app to relay through, but since
  Apple Maps IS a CarPlay app, the system may route the tap straight to
  Maps on the car display (WWDC25: widgets can launch apps in CarPlay).
- iOS keeps working via onOpenURL: the app now forwards maps:// URLs (if
  the Home Screen delivers them to the app), plus legacy fuelboard:// and
  http://maps.apple.com links from older cached timelines.
- No public API exists for a widget to detect CarPlay context, so the
  single maps:// link serves both; the app-side forward is the iOS safety
  net. 35 tests pass.

FuelBoard/FuelBoardApp.swift

@@ -9,18 +9,35 @@ struct FuelBoardApp: App {
         }
     }
 
-    /// WidgetKit widgets can only open their containing app, so a widget tap
+    /// Handles deep links that end up in the app. Widget taps arrive here in
-    /// delivers a `fuelboard://directions?lat=..&lng=..` URL here instead of
+    /// two cases:
-    /// opening Apple Maps itself. Forward it to the native Maps directions
+    ///   - legacy/cached widget timelines using the `fuelboard://` relay, or
-    /// URL (`maps://?daddr=`), which is what the app's own rows use.
+    ///   - the Home Screen delivering a `maps://` URL to the containing app
+    ///     instead of opening Maps directly (the system's choice on iOS).
+    /// Either way we forward to the native Apple Maps directions URL. The
+    /// `http://maps.apple.com` form is also handled, from very old timelines.
+    /// In CarPlay the widget uses the same `maps://` URL, which routes to
+    /// Apple Maps without ever launching this app.
     private func handleOpenURL(_ url: URL) {
-        guard url.scheme == "fuelboard",
+        guard let components = URLComponents(url: url, resolvingAgainstBaseURL: false),
-              url.host == "directions",
+              let items = components.queryItems
-              let components = URLComponents(url: url, resolvingAgainstBaseURL: false),
-              let lat = components.queryItems?.first(where: { $0.name == "lat" })?.value.flatMap(Double.init),
-              let lng = components.queryItems?.first(where: { $0.name == "lng" })?.value.flatMap(Double.init),
-              let mapsURL = URL(string: "maps://?daddr=\(lat),\(lng)&t=d")
         else { return }
+
+        // Preferred: maps://?daddr=lat,lng&t=d (also covers http://maps.apple.com).
+        if let daddr = items.first(where: { $0.name == "daddr" })?.value {
+            openMaps(daddr: daddr)
+            return
+        }
+
+        // Legacy relay: fuelboard://directions?lat=..&lng=..
+        if let lat = items.first(where: { $0.name == "lat" })?.value.flatMap(Double.init),
+           let lng = items.first(where: { $0.name == "lng" })?.value.flatMap(Double.init) {
+            openMaps(daddr: "\(lat),\(lng)")
+        }
+    }
+
+    private func openMaps(daddr: String) {
+        guard let mapsURL = URL(string: "maps://?daddr=\(daddr)&t=d") else { return }
         UIApplication.shared.open(mapsURL)
     }
 }

FuelBoardWidgets/FuelPriceWidget.swift

@@ -5,9 +5,13 @@ import AppIntents
 // FuelBoard widget — petrol stations near you.
 //   systemMedium: top 3-4 stations with price + distance, each row opens Maps
 //   systemSmall:  single station, whole widget opens Maps
-// Taps deep-link to Apple Maps directions (maps://?daddr=).
+// Taps deep-link to Apple Maps directions (maps://?daddr=). The widget uses
-// Note: on the home screen Link opens Maps directly. Inside CarPlay the widget
+// the native Maps scheme (not a custom app scheme) so that CarPlay can route
-// renders but can't launch Maps (widgets can only launch their own CarPlay app).
+// the tap straight to Apple Maps — which IS a CarPlay app — without needing
+// the containing app to launch. On the Home Screen the system either opens
+// Maps directly or delivers the URL to FuelBoard, whose onOpenURL forwards it
+// (and also still handles legacy fuelboard:// and http://maps.apple.com links
+// from older cached timelines).
 //
 // Each widget instance is configured INDEPENDENTLY via its own App Intent
 // (long-press → Edit Widget): fuel type (Unleaded/Premium/Diesel) and sort
@@ -261,7 +265,7 @@ struct FuelPriceWidgetView: View {
                     .foregroundStyle(.secondary)
             }
             ForEach(entry.stations.prefix(3)) { station in
-                Link(destination: station.widgetDirectionsURL ?? URL(string: "fuelboard://")!) {
+                Link(destination: station.widgetDirectionsURL ?? URL(string: "maps://")!) {
                     HStack(spacing: 8) {
                         Text(station.name)
                             .font(.caption.weight(.semibold))

Shared/FuelStore.swift

@@ -159,13 +159,16 @@ struct FuelStation: Identifiable, Codable, Equatable {
         URL(string: "maps://?daddr=\(lat),\(lng)&t=d")
     }
 
-    /// Widget tap URL. WidgetKit widgets can ONLY open their containing app:
+    /// Widget tap URL — the native Maps scheme (`maps://`). From the iOS Home
-    /// the system hands this URL to FuelBoard via `onOpenURL`, which then
+    /// Screen the system may either (a) open Maps directly, or (b) deliver the
-    /// forwards to Apple Maps. So the widget link uses our own registered
+    /// URL to the containing app, where FuelBoardApp.onOpenURL forwards it to
-    /// `fuelboard://` scheme rather than `maps://` (which would arrive in the
+    /// Maps. In CarPlay there is no containing app, but because `maps://`
-    /// app and be silently dropped).
+    /// targets Apple Maps — an app that IS in CarPlay — the system may route
+    /// the tap straight to the car display, bypassing the app entirely. This
+    /// is the only scheme with a chance of working in CarPlay; the old
+    /// `fuelboard://` relay is kept as a handled fallback in onOpenURL.
     var widgetDirectionsURL: URL? {
-        URL(string: "fuelboard://directions?lat=\(lat)&lng=\(lng)")
+        URL(string: "maps://?daddr=\(lat),\(lng)&t=d")
     }
 
     /// Name of the bundled brand logo asset, or nil if unknown.