openBluetoothSettings method
Opens settings so the user can enable or disable Bluetooth.
Uses a native method that tries Bluetooth-specific URLs first, then
falls back to UIApplication.openSettingsURLString when the system
rejects those (common on current iOS). Throws if nothing could be opened.
Implementation
Future<void> openBluetoothSettings() async {
try {
await _channel.invokeMethod<void>('openBluetoothSettings');
} on PlatformException catch (e) {
throw Exception(e.message ?? 'Could not open Bluetooth settings');
}
}