Implemented the NotificationLabelStyle label style in the Sample app target.

Apps/Styles/Labels/NotificationLabelStyle.swift

@@ -0,0 +1,145 @@
+import SwiftUI
+
+/// The label style for the transient in-app notification banners.
+///
+/// The style renders the label's icon next to its title, over a padded, capsule Liquid Glass background. The icon is tinted with a color
+/// matching the download event given at initialization — green for a started download, yellow for a cancelled one, and red for a
+/// failed one — and the title wears a medium-weight callout font.
+struct NotificationLabelStyle: LabelStyle {
+
+    // MARK: Properties
+
+    /// The download event whose matching color tints the label's icon.
+    private let event: AppNotification.Event
+
+    // MARK: Initializers
+
+    /// Creates a notification label style for a given download event.
+    ///
+    /// - Parameter event: The download event whose matching color tints the label's icon.
+    fileprivate init(
+        event: AppNotification.Event
+    ) {
+        self.event = event
+    }
+
+    // MARK: Methods
+
+    /// Creates the styled body of the label.
+    ///
+    /// - Parameter configuration: The properties of the label being styled.
+    public func makeBody(
+        configuration: Configuration
+    ) -> some View {
+        HStack(
+            spacing: Constant.Spacing.stack
+        ) {
+            configuration.icon
+                .font(.title3)
+                .foregroundStyle(event.imageStyle)
+
+            configuration.title
+                .font(.callout)
+                .fontWeight(.medium)
+                .foregroundStyle(.primary)
+        }
+        .padding(.vertical, Constant.Padding.vertical)
+        .padding(.horizontal, Constant.Padding.horizontal)
+        .glassEffect(
+            .regular,
+            in: .capsule
+        )
+    }
+
+}
+
+// MARK: - Styles
+
+extension LabelStyle where Self == NotificationLabelStyle {
+
+    /// The label style for the transient in-app notification banners.
+    ///
+    /// - Parameter event: The download event whose matching color tints the label's icon.
+    /// - Returns: A notification label style for the given event.
+    static func notification(
+        event: AppNotification.Event
+    ) -> NotificationLabelStyle {
+        .init(event: event)
+    }
+
+}
+
+// MARK: - AppNotification.Event+Properties
+
+private extension AppNotification.Event {
+    
+    /// The color that tints the icon of a notification label: green for a started download, yellow for a cancelled one, and red
+    /// for a failed one.
+    var imageStyle: Color {
+        switch self {
+        case .cancelled: .yellow
+        case .failed: .red
+        case .started: .green
+        }
+    }
+    
+}
+
+
+// MARK: - Constants
+
+/// The constant values used across the label style.
+private enum Constant {
+    /// The padding constants.
+    enum Padding {
+        /// The horizontal padding between a label's content and its background.
+        static let horizontal: CGFloat = 16
+        /// The vertical padding between a label's content and its background.
+        static let vertical: CGFloat = 8
+    }
+
+    /// The spacing constants.
+    enum Spacing {
+        /// The spacing between the elements of a stack.
+        static let stack: CGFloat = 16
+    }
+}
+
+// MARK: - Previews
+
+#Preview(
+    "Notification label style"
+) {
+    VStack(
+        alignment: .leading,
+        spacing: 16
+    ) {
+        Label {
+            Text(verbatim: "Downloading the speech model for Dutch (Netherlands)…")
+        } icon: {
+            Image(systemName: "arrow.down.circle")
+        }
+        .labelStyle(.notification(
+                event: .started
+        ))
+
+        Label {
+            Text(verbatim: "The speech model download for Dutch (Netherlands) was cancelled.")
+        } icon: {
+            Image(systemName: "xmark.circle")
+        }
+        .labelStyle(.notification(
+            event: .cancelled
+        ))
+
+        Label {
+            Text(verbatim: "The speech model for German (Germany) could not be downloaded.")
+        } icon: {
+            Image(systemName: "exclamationmark.triangle")
+        }
+        .labelStyle(.notification(
+            event: .failed
+        ))
+    }
+    
+}

Attendi.xcodeproj/project.pbxproj

@@ -27,6 +27,7 @@
 				Attendi/Models/AppNotification.swift,
 				"Attendi/View Models/ContentViewModel.swift",
 				Attendi/Views/ContentView.swift,
+				Styles/Labels/NotificationLabelStyle.swift,
 			);
 			target = 02870A0C2FF7EB610079EA3A /* Attendi */;
 		};