feat: support stacks of sheets

ios/TrueSheetView.swift

@@ -418,50 +418,65 @@ class TrueSheetView: UIView, RCTInvalidating, TrueSheetViewControllerDelegate {
       promise.resolve(nil)
     }
   }
+
+    private func topPresenter() -> UIViewController? {
+        reactViewController()?.topMostPresenter
+    }
 
-  func present(at index: Int, promise: Promise?, animated: Bool = true) {
-    let rvc = reactViewController()
+    func present(at index: Int, promise: Promise?, animated: Bool = true) {
+        guard let presenter = topPresenter() else {
+            promise?.reject(message: "No react view controller present.")
+            return
+        }
 
-    guard let rvc else {
-      promise?.reject(message: "No react view controller present.")
-      return
-    }
+        guard viewController.sizes.indices.contains(index) else {
+            promise?.reject(message: "Size at \(index) is not configured.")
+            return
+        }
 
-    guard viewController.sizes.indices.contains(index) else {
-      promise?.reject(message: "Size at \(index) is not configured.")
-      return
-    }
+        if isPresented {
+            if #available(iOS 15.0, *) {
+                withPresentedSheet { sheet in
+                    sheet.selectedDetentIdentifier = viewController.detentIdentifierForIndex(index)
+                    viewControllerDidChangeSize(self.viewController.currentSizeInfo)
+                    promise?.resolve(nil)
+                }
+            } else {
+                viewControllerDidChangeSize(viewController.currentSizeInfo)
+                promise?.resolve(nil)
+            }
+            return
+        }
+
+        viewController.prepareForPresentation(at: index) { [weak self] in
+            guard let self = self else { return }
 
-    if isPresented {
-      if #available(iOS 15.0, *) {
-        withPresentedSheet { sheet in
-          sheet.selectedDetentIdentifier = viewController.detentIdentifierForIndex(index)
+            self.activeIndex = index
+            self.isPresented = true
 
-          // Trigger onSizeChange event when size is changed while presenting
-          viewControllerDidChangeSize(self.viewController.currentSizeInfo)
-          promise?.resolve(nil)
+            presenter.present(self.viewController, animated: animated) {
+                if #available(iOS 15.0, *) {
+                    self.viewController.observeDrag()
+                }
+
+                let data = self.sizeInfoData(from: self.viewController.currentSizeInfo)
+                self.dispatchEvent(name: "onPresent", block: self.onPresent, data: data)
+                promise?.resolve(nil)
+            }
         }
-      } else {
-        // Trigger onSizeChange event when size is changed while presenting
-        viewControllerDidChangeSize(viewController.currentSizeInfo)
-        promise?.resolve(nil)
-      }
-    } else {
-      viewController.prepareForPresentation(at: index) {
-        // Keep track of the active index
-        self.activeIndex = index
-        self.isPresented = true
-
-        rvc.present(self.viewController, animated: animated) {
-          if #available(iOS 15.0, *) {
-            self.viewController.observeDrag()
-          }
-
-          let data = self.sizeInfoData(from: self.viewController.currentSizeInfo)
-          self.dispatchEvent(name: "onPresent", block: self.onPresent, data: data)
-          promise?.resolve(nil)
+    }
+}
+
+extension UIViewController {
+    /// Returns the view controller that should receive a new modal presentation.
+    /// Walks the hierarchy: RN root → UINavigationController → presented VCs.
+    var topMostPresenter: UIViewController {
+        var top = self
+        while let presented = top.presentedViewController {
+            top = presented
         }
-      }
+        // If we are inside a UINavigationController, present from the navigation controller
+        // so the sheet appears over the whole navigation stack.
+        return top.navigationController ?? top
     }
-  }
 }