Fix date picker in XCFramework

[ku8ar]

This PR replaces direct access to UIApplication.sharedApplication.delegate.window.rootViewController with RCTKeyWindow().rootViewController.

This change was made to ensure compatibility with modern iOS app architectures (e.g., multi-scene support introduced in iOS 13) and to fix issues when building the module as an xcframework — such as when integrating with Callstack's Enterprise Framework or other brownfield setups.