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

animation_example/analysis_options.yaml

@@ -1,12 +1,7 @@
-# This file configures the analyzer, which statically analyzes Dart code to
-# check for errors, warnings, and lints.
-#
-# The issues identified by the analyzer are surfaced in the UI of Dart-enabled
-# IDEs (https://dart.dev/tools#ides-and-editors). The analyzer can also be
-# invoked from the command line by running `flutter analyze`.
+# Lint rules for Flutter apps.
+# See https://dart.dev/guides/language/analysis-options
+include: package:flutter_lints/flutter.yaml
 
-# The following line activates a set of recommended lints for Flutter apps,
-# packages, and plugins designed to encourage good coding practices.
 analyzer:
   exclude:
     - build/**
@@ -16,23 +11,13 @@ analyzer:
     - windows/**
     - macos/**
     - linux/**
-include: package:flutter_lints/flutter.yaml
 
 linter:
-  # The lint rules applied to this project can be customized in the
-  # section below to disable rules from the `package:flutter_lints/flutter.yaml`
-  # included above or to enable additional rules. A list of all available lints
-  # and their documentation is published at
-  # https://dart-lang.github.io/linter/lints/index.html.
-  #
-  # Instead of disabling a lint rule for the entire project in the
-  # section below, it can also be suppressed for a single line of code
-  # or a specific dart file by using the `// ignore: name_of_lint` and
-  # `// ignore_for_file: name_of_lint` syntax on the line or in the file
-  # producing the lint.
   rules:
-    # avoid_print: false  # Uncomment to disable the `avoid_print` rule
-    # prefer_single_quotes: true  # Uncomment to enable the `prefer_single_quotes` rule
-
-# Additional information about this file can be found at
-# https://dart.dev/guides/language/analysis-options
+    # Noise in small sample apps; keep the code readable.
+    avoid_print: false
+    avoid_unnecessary_containers: false
+    file_names: false
+    library_private_types_in_public_api: false
+    non_constant_identifier_names: false
+    strict_top_level_inference: false

animation_example/android/app/build.gradle.kts

@@ -6,7 +6,7 @@ plugins {
 }
 
 android {
-    namespace = "com.example.penassignment"
+    namespace = "github.nisrulz.animation_example"
     compileSdk = flutter.compileSdkVersion
     ndkVersion = flutter.ndkVersion
 
@@ -16,7 +16,7 @@ android {
     }
 
     defaultConfig {
-        applicationId = "com.example.penassignment"
+        applicationId = "github.nisrulz.animation_example"
         minSdk = flutter.minSdkVersion
         targetSdk = flutter.targetSdkVersion
         versionCode = flutter.versionCode

animation_example/android/app/src/debug/AndroidManifest.xml

@@ -1,5 +1,4 @@
-<manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="com.example.penassignment">
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
     <!-- Flutter needs it to communicate with the running application
          to allow setting breakpoints, to provide hot reload, etc.
     -->

animation_example/android/app/src/main/AndroidManifest.xml

@@ -5,6 +5,7 @@
         android:icon="@mipmap/ic_launcher">
         <activity
             android:name="io.flutter.embedding.android.FlutterActivity"
+            android:exported="true"
             android:launchMode="singleTop"
             android:theme="@style/LaunchTheme"
             android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"

animation_example/android/app/src/profile/AndroidManifest.xml

@@ -1,5 +1,4 @@
-<manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="com.example.penassignment">
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
     <!-- Flutter needs it to communicate with the running application
          to allow setting breakpoints, to provide hot reload, etc.
     -->

animation_example/lib/home_page.dart

@@ -1,7 +1,8 @@
 import 'package:flutter/material.dart';
-import 'package:flutter/scheduler.dart';
 
 class HomePage extends StatefulWidget {
+  const HomePage({super.key});
+
   @override
   _HomePageState createState() => _HomePageState();
 }
@@ -42,7 +43,7 @@ class _HomePageState extends State<HomePage>
 
     return Scaffold(
       backgroundColor: Colors.white,
-      body: Container(
+      body: SizedBox(
         width: double.infinity,
         height: size.height,
         child: Stack(
@@ -52,16 +53,16 @@ class _HomePageState extends State<HomePage>
                 top: 80,
                 child: TextButton(
                     onPressed: () {},
+                    style: ButtonStyle(
+                        backgroundColor:
+                            WidgetStateProperty.all(Colors.green)),
                     child: const Text(
                       "North",
                       style: TextStyle(
                           fontSize: 18,
                           fontWeight: FontWeight.w500,
                           color: Colors.white),
-                    ),
-                    style: ButtonStyle(
-                        backgroundColor:
-                            MaterialStateProperty.all(Colors.green)))),
+                    ))),
             Positioned(
                 top: size.height * 0.48,
                 left: -15,
@@ -69,16 +70,16 @@ class _HomePageState extends State<HomePage>
                   angle: 190.1,
                   child: TextButton(
                       onPressed: () {},
+                      style: ButtonStyle(
+                          backgroundColor:
+                              WidgetStateProperty.all(Colors.green)),
                       child: const Text(
                         "East",
                         style: TextStyle(
                             fontSize: 18,
                             fontWeight: FontWeight.w500,
                             color: Colors.white),
-                      ),
-                      style: ButtonStyle(
-                          backgroundColor:
-                              MaterialStateProperty.all(Colors.green))),
+                      )),
                 )),
             Positioned(
                 top: size.height * 0.48,
@@ -87,31 +88,31 @@ class _HomePageState extends State<HomePage>
                   angle: -190.1,
                   child: TextButton(
                       onPressed: () {},
+                      style: ButtonStyle(
+                          backgroundColor:
+                              WidgetStateProperty.all(Colors.green)),
                       child: const Text(
                         "West",
                         style: TextStyle(
                             fontSize: 18,
                             fontWeight: FontWeight.w500,
                             color: Colors.white),
-                      ),
-                      style: ButtonStyle(
-                          backgroundColor:
-                              MaterialStateProperty.all(Colors.green))),
+                      )),
                 )),
             Positioned(
                 bottom: 80,
                 child: TextButton(
                     onPressed: () {},
+                    style: ButtonStyle(
+                        backgroundColor:
+                            WidgetStateProperty.all(Colors.green)),
                     child: const Text(
                       "North",
                       style: TextStyle(
                           fontSize: 18,
                           fontWeight: FontWeight.w500,
                           color: Colors.white),
-                    ),
-                    style: ButtonStyle(
-                        backgroundColor:
-                            MaterialStateProperty.all(Colors.green)))),
+                    ))),
             AnimatedBuilder(
               animation: controller,
               child: Container(

animation_example/lib/main.dart

@@ -7,7 +7,7 @@ void main() {
 }
 
 class MyApp extends StatelessWidget {
-  const MyApp({Key? key}) : super(key: key);
+  const MyApp({super.key});
 
   // This widget is the root of your application.
   @override

animation_example/pubspec.yaml

@@ -1,4 +1,4 @@
-name: penassignment
+name: animation_example
 description: A new Flutter project.
 
 # The following line prevents the package from being accidentally published to