Created .env file for environment variables and added corresponding package (flutter_dotenv)

lib/presentation/auth/auth_screen/auth_screen.dart

@@ -7,6 +7,7 @@ import 'package:validators/validators.dart';
 import 'package:eatvio_app/widgets/next_step_button.dart';
 import 'package:eatvio_app/widgets/custom_text_form_field.dart';
 import 'package:flutter/material.dart';
+import 'package:flutter_dotenv/flutter_dotenv.dart';
 import 'dart:convert';
 import 'package:hive/hive.dart';
 import 'package:http/http.dart' as http;
@@ -83,8 +84,7 @@ class AuthScreen extends StatelessWidget {
                           'password': state.passwordController!.text,
                         };
                         final response = await http.post(
-                            Uri.parse(
-                                'https://emaibo4wahye-dev3.eatvio.ru/api/login'),
+                            Uri.parse(dotenv.env['SERVER_ROOT']! + '/login'),
                             headers: {'Content-Type': 'application/json'},
                             body: json.encode(credentials),
                             encoding: utf8);
@@ -103,7 +103,7 @@ class AuthScreen extends StatelessWidget {
                             builder: (context) => AlertDialog(
                               title: Text('Ошибка'),
                               content:
-                                  Text(jsonDecode(jsonEncode(response.body))),
+                                  Text(dotenv.env['SERVER_ROOT']! + '/login'),
                               actions: [
                                 TextButton(
                                   onPressed: () {