Root component Appear not working in first time after launch

[markdevocht]

Summary

Android — ReactView: defer RNN.ComponentWillAppear / RNN.ComponentDidAppear until ReactContext is available and the Fabric surface reports content (isRendered()), so JS can bindComponent before per-screen appear events. Aligns with iOS RNNReactView (pending appear until mount). Relates to #8265 (root componentDidAppear missed on first launch).

Problem

• Instance componentDidAppear only works after Navigation.events().bindComponent(this) in mount. If native emits RNN.ComponentDidAppear before that, ComponentEventsObserver has no listeners for that componentId and the callback is dropped.
• On Android, appear could fire from ComponentViewController visibility before the surface had mounted content; iOS already defers in RNNReactView.

What changed

• android/src/main/java/com/reactnativenavigation/react/ReactView.java
  • Defer when getReactContext() == null or !isRendered()
  • Pending will/did, coalesced flush, bounded retries, degraded fallback if context exists but the surface never reports children
  • Clear deferred state on sendComponentStop and destroy