feat: bouton 'Fiche' dans la table clients vers /admin/clients/{id}

Ajout bouton indigo 'Fiche' dans la colonne Actions, avant Suspendre/Supprimer.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

templates/admin/clients/index.html.twig

@@ -82,6 +82,7 @@
                         <td class="px-4 pt-3 pb-1 text-xs text-gray-500">{{ customer.createdAt|date('d/m/Y') }}</td>
                         <td class="px-4 pt-3 pb-1 text-center">
                             <div class="flex items-center justify-center gap-2">
+                                <a href="{{ path('app_admin_clients_show', {id: customer.id}) }}" class="px-2 py-1 border-2 border-indigo-600 bg-white text-indigo-600 font-bold uppercase text-[10px] tracking-widest hover:bg-indigo-600 hover:text-white transition-all">Fiche</a>
                                 {% if not customer.isPendingDelete %}
                                     <form method="post" action="{{ path('app_admin_clients_toggle', {id: customer.id}) }}">
                                         {% if customer.isActive %}