feat: Integrate Firebase Authentication and Firestore

- Added Firebase configuration to Android and iOS projects.
- Created `google-services.json` and `GoogleService-Info.plist` for Firebase setup.
- Implemented `AuthService` for handling user authentication with Firebase.
- Updated `UserProvider` to manage user data with Firestore.
- Refactored `ProfileContent`, `LoginPage`, and `SignUpPage` to use the new authentication service.
- Removed the old `UserService` and replaced it with Firestore-based user management.
- Added Firebase options in `firebase_options.dart` for platform-specific configurations.
- Updated dependencies in `pubspec.yaml` for Firebase packages.

lib/pages/login.dart

@@ -1,5 +1,5 @@
 import 'package:flutter/material.dart';
-import '../services/user_service.dart';
+import '../services/auth_service.dart';
 import 'package:provider/provider.dart';
 import '../providers/user_provider.dart';
 
@@ -14,7 +14,7 @@ class _LoginPageState extends State<LoginPage> {
   final _formKey = GlobalKey<FormState>();
   final _emailController = TextEditingController();
   final _passwordController = TextEditingController();
-  final _userService = UserService();
+  final _authService = AuthService();
 
   bool _isLoading = false;
   bool _obscurePassword = true;
@@ -26,26 +26,6 @@ class _LoginPageState extends State<LoginPage> {
     super.dispose();
   }
 
-  // Validation de l'email
-  String? _validateEmail(String? value) {
-    if (value == null || value.trim().isEmpty) {
-      return 'Email requis';
-    }
-    final emailRegex = RegExp(r'^[\w-\.]+@([\w-]+\.)+[\w-]{2,4}$');
-    if (!emailRegex.hasMatch(value.trim())) {
-      return 'Email invalide';
-    }
-    return null;
-  }
-
-  // Validation du mot de passe
-  String? _validatePassword(String? value) {
-    if (value == null || value.isEmpty) {
-      return 'Mot de passe requis';
-    }
-    return null;
-  }
-
   // Méthode de connexion
   Future<void> _login() async {
     if (!_formKey.currentState!.validate()) {
@@ -57,24 +37,26 @@ class _LoginPageState extends State<LoginPage> {
     });
 
     try {
-      final user = await _userService.authenticateUser(
-        _emailController.text.trim(),
-        _passwordController.text,
+      final userCredential = await _authService.signIn(
+        email: _emailController.text.trim(),
+        password: _passwordController.text,
       );
 
-      if (mounted) {
-        if (user != null) {
-          // Naviguer vers la page d'accueil
-          Provider.of<UserProvider>(context, listen: false).setCurrentUser(user);
+      if (mounted && userCredential.user != null) {
+        // Récupérer les données utilisateur depuis Firestore
+        final userProvider = Provider.of<UserProvider>(context, listen: false);
+        final userData = await userProvider.getUserData(userCredential.user!.uid);
+        
+        if (userData != null) {
+          userProvider.setCurrentUser(userData);
           Navigator.pushReplacementNamed(context, '/home');
         } else {
-          // Échec de la connexion
-          _showErrorMessage('Email ou mot de passe incorrect');
+          _showErrorMessage('Données utilisateur non trouvées');
         }
       }
     } catch (e) {
       if (mounted) {
-        _showErrorMessage('Erreur lors de la connexion: ${e.toString()}');
+        _showErrorMessage('Email ou mot de passe incorrect');
       }
     } finally {
       if (mounted) {
@@ -85,18 +67,6 @@ class _LoginPageState extends State<LoginPage> {
     }
   }
 
-  void _showErrorMessage(String message) {
-    if (mounted) {
-      ScaffoldMessenger.of(context).showSnackBar(
-        SnackBar(
-          content: Text(message),
-          backgroundColor: Colors.red,
-          duration: const Duration(seconds: 3),
-        ),
-      );
-    }
-  }
-
   @override
   Widget build(BuildContext context) {
     return Scaffold(
@@ -341,4 +311,36 @@ class _LoginPageState extends State<LoginPage> {
       ),
     );
   }
+
+  // Validation de l'email
+  String? _validateEmail(String? value) {
+    if (value == null || value.trim().isEmpty) {
+      return 'Email requis';
+    }
+    final emailRegex = RegExp(r'^[\w-\.]+@([\w-]+\.)+[\w-]{2,4}$');
+    if (!emailRegex.hasMatch(value.trim())) {
+      return 'Email invalide';
+    }
+    return null;
+  }
+
+  // Validation du mot de passe
+  String? _validatePassword(String? value) {
+    if (value == null || value.isEmpty) {
+      return 'Mot de passe requis';
+    }
+    return null;
+  }
+
+  void _showErrorMessage(String message) {
+    if (mounted) {
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+          content: Text(message),
+          backgroundColor: Colors.red,
+          duration: const Duration(seconds: 3),
+        ),
+      );
+    }
+  }
 }