banner: float below nav bar (no glass pass-through) + slide-up dismiss

Position the floating banner just below the nav bar so it no longer overlays the iOS 26 Liquid Glass back/toolbar chrome behind it — tapping retry can no longer also select the control beneath. Banner now slides up + fades on dismiss/timeout (one style for all notifications); full-rect contentShape for a solid tap target.

FuelBoard/ContentView.swift

@@ -482,14 +482,22 @@ struct ContentView: View {
     }
 
     private var mainContent: some View {
-        ZStack(alignment: .top) {
-            rootTabView
-            if let banner = activeBanner {
-                // Floating above the tabs: overlays content, never pushes it.
-                floatingBanner(banner)
-                    .padding(.top, 6)
-                    .transition(.asymmetric(insertion: .move(edge: .top).combined(with: .opacity),
-                                            removal: .opacity))
+        GeometryReader { geo in
+            ZStack(alignment: .top) {
+                rootTabView
+                if let banner = activeBanner {
+                    // Floating just below the nav bar: overlays content (never
+                    // pushes it) and stays clear of the iOS 26 nav/toolbar
+                    // Liquid Glass chrome so a tap on the banner can't also
+                    // trigger the control behind it.
+                    floatingBanner(banner)
+                        .padding(.top, geo.safeAreaInsets.top + 52)
+                        .transition(.asymmetric(
+                            insertion: .move(edge: .top).combined(with: .opacity),
+                            // Slide up + fade on dismiss/timeout (one style for all).
+                            removal: .move(edge: .top).combined(with: .opacity)
+                        ))
+                }
             }
         }
         .animation(.spring(response: 0.3, dampingFraction: 0.8), value: activeBanner)
@@ -600,6 +608,7 @@ struct ContentView: View {
             )
             .padding(.horizontal, 12)
         }
+        .contentShape(Rectangle())
         .buttonStyle(.plain)
         .accessibilityLabel(accessibilityLabel)
     }