fix(android): defer initial camera events until defaults apply

[RobJacobson]

Description

On Android, the Mapbox camera-change listener can run before the <Camera defaultSettings> attachment callbacks have applied the configured camera. During that startup window, onCameraChanged can expose the SDK's temporary [0, 0] center.

Hold camera-change notifications until attachment callbacks finish, then emit one change event pair for the resulting camera state. Subsequent camera changes continue through the normal event path.

Fixes #4213

Checklist

• I've read CONTRIBUTING.md
• I updated the doc/other generated code with running yarn generate in the root folder — N/A; this Android lifecycle fix changes no generated code or docs
• I tested the fix on the /example app
  • In V11 mode/iOS — N/A; Android-only change
  • In New Architecture mode/iOS — N/A; Android-only change
  • In V11 mode/Android
  • In New Architecture mode/Android
• I added/updated a sample — N/A; this is a bug fix

Screenshot OR Video

N/A; the issue is about the values emitted during map startup.

Component to reproduce the issue you're fixing

import React from "react";
import { View } from "react-native";
import Mapbox, { Camera, MapView } from "@rnmapbox/maps";

const onCameraChanged = (mapState) => {
  const center = mapState?.properties?.center;
  if (!Array.isArray(center)) return;

  const [lng, lat] = center;
  if (lng !== 0 && lat !== 0) return;

  console.log(`COORDS ->> lng: ${lng} lat: ${lat}`);
};

export default function MapReproScreen() {
  return (
    <View style={{ flex: 1 }}>
      <MapView
        style={{ flex: 1 }}
        styleURL={Mapbox.StyleURL.Satellite}
        onCameraChanged={onCameraChanged}
      >
        <Camera
          defaultSettings={{
            centerCoordinate: [-93.265, 44.9778],
            zoomLevel: 6,
          }}
        />
      </MapView>
    </View>
  );
}

Before/after reproduction evidence

• Before the fix, the Android emulator emitted center=[0,0] during startup, followed by the configured center. The issue reporter observes the zero center twice; this reproduction run observed it once.
• After the fix, startup emitted the configured center [-93.265, 44.9778] and no [0,0] event. Panning the map continued to emit updated camera centers.

Validation evidence

• Android Kotlin compilation and the example app debug build succeeded.
• The example app was launched on an Android AVD; startup and pan behavior were checked against the reproducer.
• Jest: 27 suites and 238 tests passed.
• ESLint passed with example/build/** excluded. The unfiltered lint run reports one no-undef error for Buffer in the generated example/build/circle-native-gate/server.cjs; it is unrelated to this change.

[RobJacobson]

Closing this duplicate in favor of #4355. It follows the same Android startup camera change; #4355 preserves that fix, adds focused CameraChangeEventGate tests, and consolidates the validation record.