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

lunch_app/lib/main.dart

@@ -1,11 +1,12 @@
 import 'package:flutter/material.dart';
-import 'package:lunch_app/views/prototype/food_detail_view.dart';
 
 import 'views/prototype/home.dart';
 
 void main() => runApp(LunchApp());
 
 class LunchApp extends StatelessWidget {
+  const LunchApp({super.key});
+
   @override
   Widget build(BuildContext context) {
     return MaterialApp(

lunch_app/lib/views/prototype/bottom_nav/bottom_nav.dart

@@ -1,6 +1,8 @@
 import 'package:flutter/material.dart';
 
 class BottomNav extends StatelessWidget {
+  const BottomNav({super.key});
+
   @override
   Widget build(BuildContext context) {
     return Container(
@@ -41,7 +43,7 @@ class BottomNav extends StatelessWidget {
                 Expanded(
                   child: Icon(
                     Icons.shopping_basket,
-                    color: Colors.white.withOpacity(0.5),
+                    color: Colors.white.withValues(alpha: 0.5),
                   ),
                 ),
               ],

lunch_app/lib/views/prototype/food_detail_view.dart

@@ -1,9 +1,10 @@
-import 'dart:ui';
 
 import 'package:flutter/material.dart';
 import 'package:lunch_app/views/prototype/widgets/carousel_indicator.dart';
 
 class FoodDetailView extends StatefulWidget {
+  const FoodDetailView({super.key});
+
   @override
   _FoodDetailViewState createState() => _FoodDetailViewState();
 }

lunch_app/lib/views/prototype/home.dart

@@ -7,6 +7,8 @@ import 'package:lunch_app/views/prototype/widgets/options_selector.dart';
 import 'bottom_nav/bottom_nav.dart';
 
 class Home extends StatefulWidget {
+  const Home({super.key});
+
   @override
   _HomeState createState() => _HomeState();
 }
@@ -21,7 +23,10 @@ class _HomeState extends State<Home> {
           child: SvgPicture.asset(
             "assets/nav/drawer.svg",
             width: 25,
-            color: Colors.black.withOpacity(0.7),
+            colorFilter: ColorFilter.mode(
+              Colors.black.withValues(alpha: 0.7),
+              BlendMode.srcIn,
+            ),
           ),
         ),
       ),

lunch_app/lib/views/prototype/widgets/carousel_indicator.dart

@@ -21,7 +21,7 @@ class CarouselIndicator extends StatelessWidget {
               height: 8,
               width: 8,
               decoration: BoxDecoration(
-                color: active ? Colors.white : Colors.white.withOpacity(0.4),
+                color: active ? Colors.white : Colors.white.withValues(alpha: 0.4),
                 shape: BoxShape.circle,
               ),
               margin: const EdgeInsets.only(right: 5),

lunch_app/lib/views/prototype/widgets/food_lister.dart

@@ -2,6 +2,8 @@ import 'package:flutter/material.dart';
 import 'package:lunch_app/views/prototype/food_detail_view.dart';
 
 class FoodLister extends StatefulWidget {
+  const FoodLister({super.key});
+
   @override
   _FoodListerState createState() => _FoodListerState();
 }
@@ -12,7 +14,7 @@ class _FoodListerState extends State<FoodLister> {
 
   @override
   Widget build(BuildContext context) {
-    return Container(
+    return SizedBox(
       height: MediaQuery.of(context).size.width * 0.8,
       child: PageView.builder(
         scrollDirection: Axis.horizontal,