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

fix-keycloak-valid-uris.ps1

@@ -0,0 +1,49 @@
+# Script avec URIs valides (tirets au lieu d'underscores)
+$KeycloakUrl = "http://192.168.1.11:8180"
+$Realm = "unionflow"
+$ClientId = "unionflow-mobile"
+$ClientUuid = "67b09521-3c8d-4ab1-9d13-80af9240c64d"
+
+Write-Host "=== CORRECTION AVEC URIs VALIDES ===" -ForegroundColor Cyan
+
+try {
+    # Obtenir token admin
+    $tokenResponse = Invoke-RestMethod -Uri "$KeycloakUrl/realms/master/protocol/openid-connect/token" -Method Post -ContentType "application/x-www-form-urlencoded" -Body "username=admin&password=admin&grant_type=password&client_id=admin-cli"
+    $accessToken = $tokenResponse.access_token
+    Write-Host "✅ Token obtenu" -ForegroundColor Green
+    
+    # Récupérer le client actuel
+    $headers = @{ "Authorization" = "Bearer $accessToken" }
+    $client = Invoke-RestMethod -Uri "$KeycloakUrl/admin/realms/$Realm/clients/$ClientUuid" -Method Get -Headers $headers
+    
+    Write-Host "📋 Client actuel récupéré" -ForegroundColor Yellow
+    
+    # Mettre à jour seulement les redirect URIs
+    $client.redirectUris = @(
+        "dev.lions.unionflow-mobile://callback",
+        "dev.lions.unionflow-mobile://login-callback",
+        "dev.lions.unionflow-mobile://oauth/callback"
+    )
+    
+    $client.webOrigins = @("+")
+    
+    $clientJson = $client | ConvertTo-Json -Depth 10
+    
+    # Mettre à jour le client
+    Invoke-RestMethod -Uri "$KeycloakUrl/admin/realms/$Realm/clients/$ClientUuid" -Method Put -Headers $headers -Body $clientJson -ContentType "application/json"
+    
+    Write-Host "✅ Client mis à jour avec succès !" -ForegroundColor Green
+    Write-Host ""
+    Write-Host "Nouvelles redirect URIs (VALIDES):" -ForegroundColor Yellow
+    Write-Host "  - dev.lions.unionflow-mobile://callback" -ForegroundColor Gray
+    Write-Host "  - dev.lions.unionflow-mobile://login-callback" -ForegroundColor Gray
+    Write-Host "  - dev.lions.unionflow-mobile://oauth/callback" -ForegroundColor Gray
+    
+} catch {
+    Write-Host "❌ Erreur: $($_.Exception.Message)" -ForegroundColor Red
+    if ($_.Exception.Response) {
+        $reader = New-Object System.IO.StreamReader($_.Exception.Response.GetResponseStream())
+        $responseBody = $reader.ReadToEnd()
+        Write-Host "Détails: $responseBody" -ForegroundColor Red
+    }
+}