macos: show clickable mouse pointer when hovering over secure input

This only works on macOS 15 because it uses the new `pointerStyle` API.
I don't have the interest to backport this to older macOS versions but
I'm happy to accept a PR if someone else wants to do it.

macos/Sources/Features/Secure Input/SecureInputOverlay.swift

@@ -39,6 +39,7 @@ struct SecureInputOverlay: View {
                     .onTapGesture {
                         isPopover = true
                     }
+                    .backport.pointerStyle(.link)
                     .padding(.top, 10)
                     .padding(.trailing, 10)
                     .popover(isPresented: $isPopover, arrowEdge: .bottom) {

macos/Sources/Helpers/Backport.swift

@@ -23,3 +23,28 @@ extension Backport where Content: Scene {
         }
     }
 }
+
+extension Backport where Content: View {
+    func pointerStyle(_ style: BackportPointerStyle) -> some View {
+        if #available(macOS 15, *) {
+            return content.pointerStyle(style.official)
+        } else {
+            return content
+        }
+    }
+
+    enum BackportPointerStyle {
+        case grabIdle
+        case grabActive
+        case link
+
+        @available(macOS 15, *)
+        var official: PointerStyle {
+            switch self {
+            case .grabIdle: return .grabIdle
+            case .grabActive: return .grabActive
+            case .link: return .link
+            }
+        }
+    }
+}