implement download feature

DynamicIsland/components/Downloads/SpinningCircleDownloadView.swift

@@ -0,0 +1,28 @@
+import SwiftUI
+
+struct SpinningCircleDownloadView: View {
+    @State private var isRotating = false
+    
+    var body: some View {
+        ZStack {
+            // Gray track
+            Circle()
+                .stroke(Color.gray.opacity(0.3), lineWidth: 3.5)
+            
+            // Blue spinning segment
+            Circle()
+                .trim(from: 0, to: 0.25)
+                .stroke(
+                    Color.accentColor,
+                    style: StrokeStyle(lineWidth: 3.5, lineCap: .round)
+                )
+                .rotationEffect(Angle(degrees: isRotating ? 360 : 0))
+                .onAppear {
+                    withAnimation(.linear(duration: 1).repeatForever(autoreverses: false)) {
+                        isRotating = true
+                    }
+                }
+        }
+        .frame(width: 16, height: 16)
+    }
+}