add firebase, add screen flow

android/app/build.gradle.kts

@@ -3,6 +3,9 @@ import java.io.FileInputStream
 
 plugins {
     id("com.android.application")
+    // START: FlutterFire Configuration
+    id("com.google.gms.google-services")
+    // END: FlutterFire Configuration
     id("kotlin-android")
     // The Flutter Gradle Plugin must be applied after the Android and Kotlin Gradle plugins.
     id("dev.flutter.flutter-gradle-plugin")