refactor: standardize Dart and Android config across all 54 apps

- Bump all apps to sdk >=3.0.0 <4.0.0 and add flutter_lints + a shared
  analysis_options.yaml to every app (flutter analyze is now green repo-wide)
- Fix real compile errors in firebase_google_authentication and image_editor,
  plus deprecated APIs (Matrix4, SvgPicture.color, textScaleFactor),
  missing async 'mounted' guards, and misc lints via dart fix + manual fixes
- Align pubspec 'name' with each folder and Android namespace/applicationId
  with the documented github.nisrulz.* convention
- Convert bmi_calculator from a legacy Flutter module to a standard app
  with a proper android/ scaffold; fix missing android:exported in launcher
  manifests across 22 apps so all Android builds pass
- Untrack generated build files (GeneratedPluginRegistrant,
  .flutter-plugins-dependencies) and ignore them

firebase_google_authentication/lib/Screens/HomePage.dart

@@ -6,7 +6,7 @@ import 'package:flutter_svg/flutter_svg.dart';
 import 'package:google_fonts/google_fonts.dart';
 
 class HomePage extends StatefulWidget {
-  const HomePage({Key? key}) : super(key: key);
+  const HomePage({super.key});
 
   @override
   _HomePageState createState() => _HomePageState();
@@ -62,7 +62,7 @@ class _HomePageState extends State<HomePage> {
         Row(
           mainAxisAlignment: MainAxisAlignment.center,
           children: [
-            Container(
+            SizedBox(
               width: size.width * 0.8,
               child: ClipRRect(
                 borderRadius: BorderRadius.circular(29),
@@ -92,7 +92,7 @@ class _HomePageState extends State<HomePage> {
         SizedBox(
           height: 15,
         ),
-        Container(
+        SizedBox(
           width: size.width * 0.8,
           child: ClipRRect(
             borderRadius: BorderRadius.circular(29),

firebase_google_authentication/lib/Screens/InfoPage.dart

@@ -4,7 +4,7 @@ import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 
 class InfoPage extends StatefulWidget {
-  const InfoPage({Key? key}) : super(key: key);
+  const InfoPage({super.key});
 
   @override
   _InfoPageState createState() => _InfoPageState();
@@ -53,7 +53,7 @@ class _InfoPageState extends State<InfoPage> {
                   height: 15,
                 ),
                 Text(
-                  user!.email ?? '',
+                  user.email ?? '',
                   style: TextStyle(fontSize: 18, fontWeight: FontWeight.w500),
                 ),
               ],

firebase_google_authentication/lib/Screens/SignUpPage.dart

@@ -7,23 +7,28 @@ import 'package:google_fonts/google_fonts.dart';
 import 'package:provider/provider.dart';
 
 class SignUpPage extends StatefulWidget {
-  bool isLogin;
-  SignUpPage(this.isLogin);
+  final bool isLogin;
+  const SignUpPage(this.isLogin, {super.key});
   @override
-  _SignUpPageState createState() => _SignUpPageState(isLogin);
+  State<SignUpPage> createState() => _SignUpPageState();
 }
 
 class _SignUpPageState extends State<SignUpPage> {
-  bool isLogin;
-  _SignUpPageState(this.isLogin);
+  late bool isLogin;
+
+  @override
+  void initState() {
+    super.initState();
+    isLogin = widget.isLogin;
+  }
 
   bool loggingIn = false;
-  TextEditingController email = new TextEditingController();
-  TextEditingController password = new TextEditingController();
+  TextEditingController email = TextEditingController();
+  TextEditingController password = TextEditingController();
   bool showPassword = false;
 
   void showSnackBar() {
-    final snackBar = new SnackBar(
+    final snackBar = SnackBar(
       content: Text('Invalid Credentials!'),
       backgroundColor: Colors.red,
       padding: EdgeInsets.symmetric(horizontal: 10),
@@ -40,7 +45,7 @@ class _SignUpPageState extends State<SignUpPage> {
     final Size size = MediaQuery.of(context).size;
     return Scaffold(
       body: SingleChildScrollView(
-        child: Container(
+        child: SizedBox(
           height: size.height,
           width: double.infinity,
           child: Stack(
@@ -136,7 +141,7 @@ class _SignUpPageState extends State<SignUpPage> {
                   SizedBox(
                     height: 30,
                   ),
-                  Container(
+                  SizedBox(
                     width: size.width * 0.8,
                     child: ClipRRect(
                       borderRadius: BorderRadius.circular(29),
@@ -147,11 +152,11 @@ class _SignUpPageState extends State<SignUpPage> {
                           backgroundColor: Color(0xFF6F35A5),
                         ),
                         onPressed: () {
-                          String _email = email.text;
-                          String _password = password.text;
+                          String emailText = email.text;
+                          String passwordText = password.text;
                           !(isLogin)
-                              ? signUpClicked(_email, _password, context)
-                              : loginClicked(_email, _password, context);
+                              ? signUpClicked(emailText, passwordText, context)
+                              : loginClicked(emailText, passwordText, context);
                         },
                         child: Text(
                           (isLogin) ? 'Login' : 'SignUp',
@@ -166,7 +171,7 @@ class _SignUpPageState extends State<SignUpPage> {
                   SizedBox(
                     height: 18,
                   ),
-                  Container(
+                  SizedBox(
                     width: size.width * 0.81,
                     child: ClipRRect(
                       borderRadius: BorderRadius.circular(29),
@@ -181,6 +186,7 @@ class _SignUpPageState extends State<SignUpPage> {
                               context,
                               listen: false);
                           provider.googleLogin().then((value) {
+                            if (!context.mounted) return;
                             Navigator.popUntil(
                                 context, (route) => route.isFirst);
                           }).catchError((onError) {
@@ -242,14 +248,15 @@ class _SignUpPageState extends State<SignUpPage> {
     );
   }
 
-  signUpClicked(String _email, String _password, BuildContext context) {
+  void signUpClicked(String email, String password, BuildContext context) {
     FirebaseAuth.instance
-        .createUserWithEmailAndPassword(email: _email, password: _password)
+        .createUserWithEmailAndPassword(email: email, password: password)
         .then((value) {
       setState(() {
         loggingIn = true;
       });
       Future.delayed(Duration(seconds: 1, milliseconds: 50), () {
+        if (!context.mounted) return;
         Navigator.popUntil(context, (route) => route.isFirst);
       });
     }).catchError((e) {
@@ -257,14 +264,15 @@ class _SignUpPageState extends State<SignUpPage> {
     });
   }
 
-  bool loginClicked(String _email, String _password, BuildContext context) {
+  bool loginClicked(String email, String password, BuildContext context) {
     FirebaseAuth.instance
-        .signInWithEmailAndPassword(email: _email, password: _password)
+        .signInWithEmailAndPassword(email: email, password: password)
         .then((value) {
       setState(() {
         loggingIn = true;
       });
       Future.delayed(Duration(seconds: 1, milliseconds: 50), () {
+        if (!context.mounted) return;
         Navigator.pop(context);
       });
     }).catchError((e) {

firebase_google_authentication/lib/Services/google_auth.dart

@@ -15,10 +15,9 @@ class GoogleSignInProvider extends ChangeNotifier {
     try {
       await googleSignIn.initialize();
       final googleUser = await googleSignIn.authenticate();
-      if (googleUser == null) return;
       _user = googleUser;
 
-      final googleAuth = await googleUser.authentication;
+      final googleAuth = googleUser.authentication;
 
       final credentials = GoogleAuthProvider.credential(
         idToken: googleAuth.idToken,

firebase_google_authentication/lib/main.dart

@@ -11,7 +11,7 @@ void main() async{
 }
 
 class MyApp extends StatelessWidget {
-  const MyApp({Key? key}) : super(key: key);
+  const MyApp({super.key});
 
   @override
   Widget build(BuildContext context) {