feat(mobile): Implement Keycloak WebView authentication with HTTP callback

- Replace flutter_appauth with custom WebView implementation to resolve deep link issues
- Add KeycloakWebViewAuthService with integrated WebView for seamless authentication
- Configure Android manifest for HTTP cleartext traffic support
- Add network security config for development environment (192.168.1.11)
- Update Keycloak client to use HTTP callback endpoint (http://192.168.1.11:8080/auth/callback)
- Remove obsolete keycloak_auth_service.dart and temporary scripts
- Clean up dependencies and regenerate injection configuration
- Tested successfully on multiple Android devices (Xiaomi 2201116TG, SM A725F)

BREAKING CHANGE: Authentication flow now uses WebView instead of external browser
- Users will see Keycloak login page within the app instead of browser redirect
- Resolves ERR_CLEARTEXT_NOT_PERMITTED and deep link state management issues
- Maintains full OIDC compliance with PKCE flow and secure token storage

Technical improvements:
- WebView with custom navigation delegate for callback handling
- Automatic token extraction and user info parsing from JWT
- Proper error handling and user feedback
- Consistent authentication state management across app lifecycle

create-unionflow-user.ps1

@@ -0,0 +1,128 @@
+# Script pour créer un utilisateur de test dans le realm unionflow
+param(
+    [string]$KeycloakUrl = "http://192.168.1.11:8180",
+    [string]$Realm = "unionflow",
+    [string]$AdminUser = "admin",
+    [string]$AdminPassword = "admin",
+    [string]$Username = "testuser",
+    [string]$Password = "password123",
+    [string]$Email = "test@unionflow.com",
+    [string]$FirstName = "Test",
+    [string]$LastName = "User"
+)
+
+Write-Host "👤 Création d'un utilisateur de test dans Keycloak..." -ForegroundColor Cyan
+Write-Host "📍 Keycloak URL: $KeycloakUrl" -ForegroundColor Gray
+Write-Host "🏛️ Realm: $Realm" -ForegroundColor Gray
+Write-Host "👤 Username: $Username" -ForegroundColor Gray
+Write-Host ""
+
+try {
+    # 1. Obtenir le token d'administration
+    Write-Host "🔑 Obtention du token d'administration..." -ForegroundColor Yellow
+    
+    $tokenBody = @{
+        username = $AdminUser
+        password = $AdminPassword
+        grant_type = "password"
+        client_id = "admin-cli"
+    }
+    
+    $tokenResponse = Invoke-RestMethod -Uri "$KeycloakUrl/realms/master/protocol/openid-connect/token" `
+                                      -Method Post `
+                                      -ContentType "application/x-www-form-urlencoded" `
+                                      -Body $tokenBody
+    
+    $accessToken = $tokenResponse.access_token
+    Write-Host "✅ Token obtenu avec succès" -ForegroundColor Green
+    
+    # 2. Créer l'utilisateur
+    Write-Host "👤 Création de l'utilisateur '$Username'..." -ForegroundColor Yellow
+    
+    $userConfig = @{
+        username = $Username
+        email = $Email
+        firstName = $FirstName
+        lastName = $LastName
+        enabled = $true
+        emailVerified = $true
+    } | ConvertTo-Json
+    
+    $headers = @{
+        "Authorization" = "Bearer $accessToken"
+        "Content-Type" = "application/json"
+    }
+    
+    try {
+        $userResponse = Invoke-RestMethod -Uri "$KeycloakUrl/admin/realms/$Realm/users" `
+                                         -Method Post `
+                                         -Headers $headers `
+                                         -Body $userConfig
+        Write-Host "✅ Utilisateur créé avec succès" -ForegroundColor Green
+    }
+    catch {
+        if ($_.Exception.Response.StatusCode -eq 409) {
+            Write-Host "⚠️ L'utilisateur existe déjà, mise à jour..." -ForegroundColor Yellow
+        }
+        else {
+            throw
+        }
+    }
+    
+    # 3. Obtenir l'ID de l'utilisateur
+    Write-Host "🔍 Recherche de l'utilisateur..." -ForegroundColor Yellow
+    
+    $usersResponse = Invoke-RestMethod -Uri "$KeycloakUrl/admin/realms/$Realm/users?username=$Username" `
+                                      -Method Get `
+                                      -Headers $headers
+    
+    if ($usersResponse.Count -eq 0) {
+        throw "Utilisateur non trouvé après création"
+    }
+    
+    $userId = $usersResponse[0].id
+    Write-Host "✅ Utilisateur trouvé: $userId" -ForegroundColor Green
+    
+    # 4. Définir le mot de passe
+    Write-Host "🔒 Définition du mot de passe..." -ForegroundColor Yellow
+    
+    $passwordConfig = @{
+        type = "password"
+        value = $Password
+        temporary = $false
+    } | ConvertTo-Json
+    
+    Invoke-RestMethod -Uri "$KeycloakUrl/admin/realms/$Realm/users/$userId/reset-password" `
+                      -Method Put `
+                      -Headers $headers `
+                      -Body $passwordConfig
+    
+    Write-Host "✅ Mot de passe défini avec succès" -ForegroundColor Green
+    
+    Write-Host ""
+    Write-Host "🎉 UTILISATEUR CRÉÉ AVEC SUCCÈS !" -ForegroundColor Green
+    Write-Host "📧 Email: $Email" -ForegroundColor White
+    Write-Host "👤 Username: $Username" -ForegroundColor White
+    Write-Host "🔒 Password: $Password" -ForegroundColor White
+    Write-Host ""
+    Write-Host "Vous pouvez maintenant vous connecter via l'application mobile !" -ForegroundColor Cyan
+    
+}
+catch {
+    Write-Host ""
+    Write-Host "❌ ERREUR lors de la création de l'utilisateur !" -ForegroundColor Red
+    Write-Host "Détails: $($_.Exception.Message)" -ForegroundColor Red
+    
+    if ($_.Exception.Response) {
+        $statusCode = $_.Exception.Response.StatusCode.value__
+        Write-Host "Code de statut HTTP: $statusCode" -ForegroundColor Red
+    }
+    
+    Write-Host ""
+    Write-Host "Solutions possibles:" -ForegroundColor Yellow
+    Write-Host "1. Verifiez que Keycloak est accessible sur $KeycloakUrl" -ForegroundColor Gray
+    Write-Host "2. Verifiez que le realm '$Realm' existe" -ForegroundColor Gray
+    Write-Host "3. Verifiez les identifiants admin (admin/admin)" -ForegroundColor Gray
+    
+    exit 1
+}