fix(macos): expand menu hover highlight width

apps/macos/Sources/Clawdis/MenuHighlightedHostView.swift

@@ -55,6 +55,7 @@ final class HighlightedMenuItemHostView: NSView {
 
     override func layout() {
         super.layout()
+        self.updateTargetWidthFromWindow()
         self.hosting.frame = self.bounds
     }
 
@@ -83,6 +84,18 @@ final class HighlightedMenuItemHostView: NSView {
         let size = self.hosting.fittingSize
         self.frame = NSRect(origin: .zero, size: NSSize(width: self.targetWidth, height: size.height))
     }
+
+    override func viewDidMoveToWindow() {
+        super.viewDidMoveToWindow()
+        self.updateTargetWidthFromWindow()
+    }
+
+    private func updateTargetWidthFromWindow() {
+        guard let width = self.window?.contentView?.bounds.width, width > 0 else { return }
+        if abs(width - self.targetWidth) < 0.5 { return }
+        self.targetWidth = width
+        self.updateSizing()
+    }
 }
 
 struct MenuHostedHighlightedItem: NSViewRepresentable {