fix(#153): peaufiner cartes dossiers et recherche.

Cartes neutres avec accent icône, photo AM si dispo, hint court
et infobulle de critères sur la barre de recherche.

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

frontend/lib/widgets/admin/dossier_list_card.dart

@@ -1,19 +1,20 @@
 import 'package:flutter/material.dart';
 import 'package:p_tits_pas/widgets/admin/common/admin_user_card.dart';
 
-/// Carte dossier unifiée (#153) — pending et liste complète.
+/// Carte dossier unifiée (#153) — fond neutre, accent couleur sur l’icône.
 class DossierListCard extends StatelessWidget {
   final String numeroDossier;
   final String namesLine;
   final bool isFamille;
   final VoidCallback onOpen;
+  /// Photo AM (si absente → icône fallback).
+  final String? photoUrl;
 
-  static const Color familleBg = Color(0xFFF3EEF8);
-  static const Color familleBorder = Color(0xFFB39DDB);
-  static const Color familleAccent = Color(0xFF7E57C2);
-  static const Color amBg = Color(0xFFE8F5F3);
-  static const Color amBorder = Color(0xFF80CBC4);
-  static const Color amAccent = Color(0xFF00897B);
+  /// Lavande — Famille / Parents.
+  static const Color familleAccent = Color(0xFFB289C9);
+
+  /// Menthe logo — AM.
+  static const Color amAccent = Color(0xFF5A9D94);
 
   const DossierListCard({
     super.key,
@@ -21,24 +22,24 @@ class DossierListCard extends StatelessWidget {
     required this.namesLine,
     required this.isFamille,
     required this.onOpen,
+    this.photoUrl,
   });
 
   @override
   Widget build(BuildContext context) {
-    final bg = isFamille ? familleBg : amBg;
-    final border = isFamille ? familleBorder : amBorder;
     final accent = isFamille ? familleAccent : amAccent;
     final num = numeroDossier.trim().isEmpty ? '–' : numeroDossier.trim();
     final names = namesLine.trim();
+    final avatar = (photoUrl ?? '').trim();
 
     return AdminUserCard(
       title: num,
       subtitleLines: names.isEmpty ? const [] : [names],
+      avatarUrl: !isFamille && avatar.isNotEmpty ? avatar : null,
       fallbackIcon:
-          isFamille ? Icons.family_restroom_outlined : Icons.person_outline,
-      backgroundColor: bg,
-      borderColor: border,
-      titleColor: accent,
+          isFamille ? Icons.family_restroom_outlined : Icons.face,
+      // N° = titre neutre (comme Parents / AM) ; accent = icône seule.
+      avatarIconColor: accent,
       infoColor: Colors.black87,
       onCardTap: onOpen,
       actions: [