fix(ios): adopt UIScene lifecycle for iOS 27 (1.3.6 build 20)

[markm39]

Problem

1.3.4 and 1.3.5 crash at launch on iOS 27 (black screen, then the app closes). Xcode Organizer: 6 devices, all iOS 27.0.1:

`EXC_BREAKPOINT` in `___UIApplicationEvaluateRuntimeIssueForNoSceneLifecycleAdoption_block_invoke`, about 0.2 s after launch.

iOS 27 refuses to launch apps built with the iOS 27 SDK unless they adopt the UIScene lifecycle. 1.3.3 was built with an older SDK. 1.3.4 and 1.3.5 were archived with Xcode 27 (`DTSDKName iphoneos27.0`).

Fix

• `Info.plist`: `UIApplicationSceneManifest` with a single `SceneDelegate`.
• `SceneDelegate` creates the window and starts React Native. The launch URL and user activity are passed through `launchOptions`, so `Linking.getInitialURL` (Open in OpenNotes for PDFs) keeps working. Later URLs and universal links are forwarded to `RCTLinkingManager`.
• `AppDelegate` still creates the React Native factory but no longer starts React Native itself.
• Version 1.3.6 (20).

Verification (iPad Pro 11" M4 simulator, iOS 27.0, Release build, Xcode 27 SDK)

• Before (current main): fails to launch with `UIScene life cycle is required for apps built with this SDK`, `SIGTRAP`. Same as the field crash.
• After: launches; onboarding, library, the create menu, keyboard input, a new note, finger drawing, autosave ("saved") and a full relaunch with the note and its preview intact all work.