♻️ Replace bitsdojo_window with window_manager

macos/Runner/MainFlutterWindow.swift

@@ -1,12 +1,7 @@
 import Cocoa
 import FlutterMacOS
-import bitsdojo_window_macos
-
-class MainFlutterWindow: BitsdojoWindow {
-  override func bitsdojo_window_configure() -> UInt {
-    return BDW_CUSTOM_FRAME | BDW_HIDE_ON_STARTUP
-  }
 
+class MainFlutterWindow: NSWindow {
   override func awakeFromNib() {
     let flutterViewController = FlutterViewController()
     let windowFrame = self.frame
@@ -17,4 +12,4 @@ class MainFlutterWindow: BitsdojoWindow {
 
     super.awakeFromNib()
   }
-}
+}