feat: add custom cursor support for classic skins

Signed-off-by: Hans Kokx <hans.d.kokx@gmail.com>

macos/Runner/AppDelegate.swift

@@ -53,6 +53,9 @@ class AppDelegate: FlutterAppDelegate {
 
   private var _winampChannel: FlutterMethodChannel?
 
+  /// Custom cursors registered by the Dart side, keyed by skin cursor name.
+  private var cursors: [String: NSCursor] = [:]
+
   private func handleMethodCall(_ call: FlutterMethodCall, result: @escaping FlutterResult) {
     switch call.method {
     case "setAlwaysOnTop":
@@ -81,6 +84,25 @@ class AppDelegate: FlutterAppDelegate {
         setUiScaleMenuState(scale)
       }
       result(nil)
+    case "registerCursor":
+      if let args = call.arguments as? [String: Any],
+        let name = args["name"] as? String,
+        let pngData = (args["png"] as? FlutterStandardTypedData)?.data,
+        let image = NSImage(data: pngData) {
+        let hotX = args["hotspotX"] as? Int ?? 0
+        let hotY = args["hotspotY"] as? Int ?? 0
+        cursors[name] = NSCursor(image: image, hotSpot: NSPoint(x: hotX, y: hotY))
+      }
+      result(nil)
+    case "setCursor":
+      if let args = call.arguments as? [String: Any], let name = args["name"] as? String {
+        if let cursor = cursors[name] {
+          cursor.set()
+        } else {
+          NSCursor.arrow.set()
+        }
+      }
+      result(nil)
     default:
       result(FlutterMethodNotImplemented)
     }