merge: squash develop into master

Intègre en un seul commit les évolutions récentes de develop vers master, incluant la modale admin/gestionnaire, les protections super admin, les ajustements API associés et la mise à jour documentaire des tickets/spec.

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

frontend/lib/widgets/admin/common/admin_user_card.dart

@@ -6,6 +6,10 @@ class AdminUserCard extends StatefulWidget {
   final String? avatarUrl;
   final IconData fallbackIcon;
   final List<Widget> actions;
+  final Color? borderColor;
+  final Color? backgroundColor;
+  final Color? titleColor;
+  final Color? infoColor;
 
   const AdminUserCard({
     super.key,
@@ -14,6 +18,10 @@ class AdminUserCard extends StatefulWidget {
     this.avatarUrl,
     this.fallbackIcon = Icons.person,
     this.actions = const [],
+    this.borderColor,
+    this.backgroundColor,
+    this.titleColor,
+    this.infoColor,
   });
 
   @override
@@ -43,9 +51,10 @@ class _AdminUserCardState extends State<AdminUserCard> {
           child: Card(
             margin: const EdgeInsets.only(bottom: 12),
             elevation: 0,
+            color: widget.backgroundColor,
             shape: RoundedRectangleBorder(
               borderRadius: BorderRadius.circular(10),
-              side: BorderSide(color: Colors.grey.shade300),
+              side: BorderSide(color: widget.borderColor ?? Colors.grey.shade300),
             ),
             child: Padding(
               padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 9),
@@ -76,7 +85,7 @@ class _AdminUserCardState extends State<AdminUserCard> {
                             style: const TextStyle(
                               fontWeight: FontWeight.w600,
                               fontSize: 14,
-                            ),
+                            ).copyWith(color: widget.titleColor),
                             maxLines: 1,
                             overflow: TextOverflow.ellipsis,
                           ),
@@ -88,7 +97,7 @@ class _AdminUserCardState extends State<AdminUserCard> {
                             style: const TextStyle(
                               color: Colors.black54,
                               fontSize: 12,
-                            ),
+                            ).copyWith(color: widget.infoColor),
                             maxLines: 1,
                             overflow: TextOverflow.ellipsis,
                           ),