macos: add needsConfirmQuit helper to surface and split structs

macos/Sources/Ghostty/Ghostty.SplitView.swift

@@ -96,6 +96,22 @@ extension Ghostty {
                 container.bottomRight.close()
             }
         }
+        
+        /// Returns true if any surface in the split stack requires quit confirmation.
+        func needsConfirmQuit() -> Bool {
+            switch (self) {
+            case .noSplit(let leaf):
+                return leaf.surface.needsConfirmQuit
+
+            case .horizontal(let container):
+                return container.topLeft.needsConfirmQuit() ||
+                    container.bottomRight.needsConfirmQuit()
+
+            case .vertical(let container):
+                return container.topLeft.needsConfirmQuit() ||
+                    container.bottomRight.needsConfirmQuit()
+            }
+        }
 
         /// Returns true if the split tree contains the given view.
         func contains(view: SurfaceView) -> Bool {

macos/Sources/Ghostty/SurfaceView.swift

@@ -252,6 +252,13 @@ extension Ghostty {
         // then the view is moved to a new window.
         var initialSize: NSSize? = nil
         
+        // Returns true if quit confirmation is required for this surface to
+        // exit safely.
+        var needsConfirmQuit: Bool {
+            guard let surface = self.surface else { return false }
+            return ghostty_surface_needs_confirm_quit(surface)
+        }
+        
         // Returns the inspector instance for this surface, or nil if the
         // surface has been closed.
         var inspector: ghostty_inspector_t? {