Figure out a way to receive sms received event regardless of whether the app is running or not.

[shounakmulay]

• https://github.com/avioli/uni_links/blob/master/android/src/main/java/name/avioli/unilinks/UniLinksPlugin.java

• https://github.com/FirebaseExtended/flutterfire/blob/master/packages/firebase_messaging/android/src/main/java/io/flutter/plugins/firebasemessaging/FirebaseMessagingPlugin.java

• https://github.com/flutter/plugins/blob/master/packages/android_alarm_manager/android/src/main/java/io/flutter/plugins/androidalarmmanager/FlutterBackgroundExecutor.java

• https://github.com/vrtdev/flutter_workmanager