When the runtime is reloaded in-process (NativeScriptRuntime.reloadApplication, used for OTA soft reboots) the app re-runs main in a fresh JS isolate while the process stays alive. iOSApplication.run() sees a live UIApplication and routes to runAsEmbeddedApp()

• The previous UIWindow was deallocated along with the old isolate (it was retained only by the JS-side SceneDelegate._window), and sceneWillConnectToSession, which creates the window, does not re-fire on a reload. getWindow() then returned null and runAsEmbeddedApp() bailed early, leaving a black screen.
• With no embedder delegate (NativeScript owns the UIApplication), the new root was presented modally over the old, now-dead root controller instead of replacing it, leaking the old controller on every reload and breaking when an overlay is mid-presentation.

runAsEmbeddedApp() works same as before but now supports this use case:

• recreates a window bound to the active UIWindowScene when none is found (initWithWindowScene + _setWindowForScene/_setupWindowForScene);
• moves the rootViewController guard into the embedder-only branch, since a freshly recreated window has no controller yet;
• replaces the window root via setWindowRootView() for the NativeScript-owned case

Supports 9.1 runtime features for OTA installed hot reloading of runtime isolates.