feat(#112): reprise après refus via lien e-mail (/reprise?token=)

Branche le flux front : chargement du dossier, session reprise, wizards
parent/AM préremplis et resoumission via reprise-resoumettre.

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/lib/screens/auth/am_register_step4_screen.dart

@@ -8,6 +8,7 @@ import '../../models/am_registration_data.dart';
 import '../../models/card_assets.dart';
 import '../../config/display_config.dart';
 import '../../services/auth_service.dart';
+import '../../services/reprise_session.dart';
 import '../../widgets/hover_relief_widget.dart';
 import '../../widgets/image_button.dart';
 import '../../widgets/custom_navigation_button.dart';
@@ -27,7 +28,21 @@ class _AmRegisterStep4ScreenState extends State<AmRegisterStep4Screen> {
 
   Future<void> _submitAMRegistration(AmRegistrationData registrationData) async {
     if (_isSubmitting) return;
-    if (!registrationData.isRegistrationComplete) {
+    if (RepriseSession.isActive) {
+      if (!registrationData.isRepriseSubmitReady) {
+        if (!mounted) return;
+        ScaffoldMessenger.of(context).showSnackBar(
+          SnackBar(
+            content: Text(
+              'Vérifiez vos coordonnées et acceptez les conditions.',
+              style: GoogleFonts.merienda(fontSize: 14),
+            ),
+            backgroundColor: Colors.red.shade700,
+          ),
+        );
+        return;
+      }
+    } else if (!registrationData.isRegistrationComplete) {
       if (!mounted) return;
       ScaffoldMessenger.of(context).showSnackBar(
         SnackBar(
@@ -42,6 +57,22 @@ class _AmRegisterStep4ScreenState extends State<AmRegisterStep4Screen> {
     }
     setState(() => _isSubmitting = true);
     try {
+      if (RepriseSession.isActive) {
+        await AuthService.resoumettreReprise(
+          token: RepriseSession.token!,
+          prenom: registrationData.firstName,
+          nom: registrationData.lastName,
+          telephone: registrationData.phone,
+          adresse: registrationData.streetAddress,
+          ville: registrationData.city,
+          codePostal: registrationData.postalCode,
+          photoUrl: RepriseSession.photoUrl,
+        );
+        RepriseSession.clear();
+        if (!mounted) return;
+        _showRepriseConfirmationModal(context);
+        return;
+      }
       await AuthService.registerAM(registrationData);
       if (!mounted) return;
       _showConfirmationModal(context);
@@ -244,6 +275,34 @@ class _AmRegisterStep4ScreenState extends State<AmRegisterStep4Screen> {
     );
   }
 
+  void _showRepriseConfirmationModal(BuildContext context) {
+    showDialog<void>(
+      context: context,
+      barrierDismissible: false,
+      builder: (BuildContext dialogContext) {
+        return AlertDialog(
+          title: Text(
+            'Dossier resoumis',
+            style: GoogleFonts.merienda(fontWeight: FontWeight.bold),
+          ),
+          content: Text(
+            'Vos modifications ont été enregistrées. Votre dossier est de nouveau en attente de validation.',
+            style: GoogleFonts.merienda(fontSize: 14),
+          ),
+          actions: <Widget>[
+            TextButton(
+              child: Text('OK', style: GoogleFonts.merienda(fontWeight: FontWeight.bold)),
+              onPressed: () {
+                Navigator.of(dialogContext).pop();
+                context.go('/login');
+              },
+            ),
+          ],
+        );
+      },
+    );
+  }
+
   void _showConfirmationModal(BuildContext context) {
     showDialog<void>(
       context: context,