Use native large-title behaviour: drop custom icon header, .navigationTitle + .large (exact Mail-style collapse)

FuelBoard/StationsView.swift

@@ -22,35 +22,10 @@ struct StationsView: View {
     /// which station is "best".
     @State private var pageSize = 10
     @State private var visibleCount = 10
-    /// True once the list has scrolled — the large header title is shown at
-    /// rest; the compact gas-pump+title bar appears only after scrolling.
-    @State private var isScrolled = false
 
     var body: some View {
         NavigationStack {
-            VStack(spacing: 0) {
-                // Large pinned title — Mail-style. It stays in place above the
-                // list (content scrolls beneath it) and fades out in place
-                // once scrolling starts, while the compact icon+title bar fades
-                // in below the nav bar. Keeping it OUT of the List means the
-                // fade isn't masked by the row scrolling away.
-                HStack(spacing: 10) {
-                    Image(systemName: "fuelpump.fill")
-                        .font(.system(size: 34))
-                        .foregroundStyle(selectedFuel.tintColor)
-                    Text("FuelBoard")
-                        .font(.largeTitle.bold())
-                }
-                .frame(maxWidth: .infinity, alignment: .leading)
-                .padding(.horizontal, 16)
-                .padding(.vertical, 6)
-                .frame(height: isScrolled ? 0 : 54, alignment: .top)
-                .clipped()
-                .background(Color(.systemGroupedBackground))
-                .opacity(isScrolled ? 0 : 1)
-                .animation(.easeInOut(duration: 0.2), value: isScrolled)
-
-                List {
+            List {
                 Section {
                     if let location {
                         if sortMode == .closest {
@@ -205,51 +180,18 @@ struct StationsView: View {
                 // New fetch or filter switch → back to the first page.
                 visibleCount = pageSize
             }
-            .modifier(ScrolledTracker(isScrolled: $isScrolled))
-            .toolbar {
-                ToolbarItem(placement: .principal) {
-                    if isScrolled {
-                        HStack(spacing: 6) {
-                            Image(systemName: "fuelpump.fill")
-                                .foregroundStyle(selectedFuel.tintColor)
-                            Text("FuelBoard")
-                                .font(.headline)
-                        }
-                        .transition(.opacity)
-                    }
-                }
-            }
-            .navigationBarTitleDisplayMode(.inline)
-            }
+            // Native large-title behaviour (Mail-style): the system shows the
+            // large title at rest, scrolls it away and fades the compact
+            // inline title in. No custom toolbar needed — the native mechanism
+            // only renders text, which is exactly what we want here.
+            .navigationTitle("FuelBoard")
+            .navigationBarTitleDisplayMode(.large)
         }
     }
 }
 
 // MARK: - Fuel-type iconography (app target only — FuelStore.swift is Foundation-only)
 
-/// Tracks whether the list has scrolled, using the native scroll-geometry API
-/// (iOS 18+) — the reliable way to know when the large header title has
-/// collapsed. (The old GeometryReader-preference approach didn't fire in List,
-/// which is why the compact bar never appeared.)
-private struct ScrolledTracker: ViewModifier {
-    @Binding var isScrolled: Bool
-
-    func body(content: Content) -> some View {
-        if #available(iOS 18.0, *) {
-            content
-                .onScrollGeometryChange(for: Bool.self) { geometry in
-                    geometry.contentOffset.y > 40
-                } action: { _, scrolled in
-                    withAnimation(.easeInOut(duration: 0.2)) {
-                        isScrolled = scrolled
-                    }
-                }
-        } else {
-            content
-        }
-    }
-}
-
 extension FuelType {
     /// Short segment label ("Unleaded" / "Premium" / "Diesel") for the picker.
     var shortName: String {