feat(#173): icône dessin en haut à droite selon le type de bulle

Congés / arrêt maladie / absence — assets remplaçables dans
assets/images/cartes/.

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

frontend/lib/models/carte_bulle.dart

@@ -104,6 +104,21 @@ class CarteBulle {
   bool get isArretMaladie => typeCode == 'arret_maladie_am';
   bool get isCongeAm => typeCode == 'conge_am';
 
+  /// Icône dessin (haut droite) selon le type de bulle.
+  String? get iconAsset {
+    switch (typeCode) {
+      case 'conge_am':
+        return 'assets/images/cartes/icon_carte_conges.png';
+      case 'arret_maladie_am':
+        return 'assets/images/cartes/icon_carte_maladie.png';
+      case 'absence_enfant':
+      case 'absence_enfant_modif':
+        return 'assets/images/cartes/icon_carte_absence.png';
+      default:
+        return null;
+    }
+  }
+
   /// Fin de période (jour inclus). Null si dates absentes / invalides.
   DateTime? get dateFinJour {
     final raw = dateFin;

frontend/lib/widgets/quotidien/cartes_feed.dart

@@ -383,15 +383,31 @@ class _BulleTile extends StatelessWidget {
         child: Column(
           crossAxisAlignment: CrossAxisAlignment.stretch,
           children: [
-            Text(
-              card.titreAffiche,
-              maxLines: 1,
-              overflow: TextOverflow.ellipsis,
-              style: GoogleFonts.merienda(
-                fontSize: 18,
-                fontWeight: FontWeight.w700,
-                color: QuotidienTheme.ink,
-              ),
+            Row(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Expanded(
+                  child: Text(
+                    card.titreAffiche,
+                    maxLines: 2,
+                    overflow: TextOverflow.ellipsis,
+                    style: GoogleFonts.merienda(
+                      fontSize: 18,
+                      fontWeight: FontWeight.w700,
+                      color: QuotidienTheme.ink,
+                    ),
+                  ),
+                ),
+                if (card.iconAsset != null) ...[
+                  const SizedBox(width: 8),
+                  Image.asset(
+                    card.iconAsset!,
+                    width: 44,
+                    height: 44,
+                    fit: BoxFit.contain,
+                  ),
+                ],
+              ],
             ),
             if (card.dateDebut != null || card.dateFin != null) ...[
               const SizedBox(height: 10),