fix: scope control fades to preserve responsive window animation

Sources/App/CompactWindow.swift

@@ -1,4 +1,5 @@
 import AppKit
+import QuartzCore
 
 @MainActor
 final class CompactWindowController: NSObject {
@@ -378,10 +379,10 @@ final class CompactWindowController: NSObject {
         frameAnimationGeneration &+= 1
         let generation = frameAnimationGeneration
         frameAnimating = true
-        // Coordinate the resize through NSWindow. Its animator proxy races SwiftUI's
-        // animated window sizing and can re-enter layout until AppKit aborts.
-        NSAnimationContext.runAnimationGroup { _ in
-            window.setFrame(frame, display: true, animate: true)
+        NSAnimationContext.runAnimationGroup { context in
+            context.duration = Self.transitionDuration
+            context.timingFunction = CAMediaTimingFunction(name: .easeInEaseOut)
+            window.animator().setFrame(frame, display: true)
         } completionHandler: { [weak self, weak window] in
             MainActor.assumeIsolated {
                 guard let self, let window, self.window === window, self.frameAnimating,
@@ -396,7 +397,11 @@ final class CompactWindowController: NSObject {
         guard frameAnimating else { return }
         frameAnimating = false
         frameAnimationGeneration &+= 1
-        // Native resize animation has returned; invalidate only its pending completion.
+        guard let window else { return }
+        NSAnimationContext.runAnimationGroup { context in
+            context.duration = 0
+            window.animator().setFrame(window.frame, display: true)
+        }
     }
 
     private func setState(compact: Bool, transitioning: Bool) {