style(ui): change default button size from sm to md and remove explicit size="sm" props

src/features/admin/components/AdminHeader.js

@@ -18,7 +18,7 @@ const AdminHeader = ({ title, description, backHref, backLabel = '← Retour', a
       </div>
       <div className='flex gap-2'>
         {backHref && (
-          <Button variant="secondary" size="sm" onClick={() => router.push(backHref)}>
+          <Button variant="secondary" onClick={() => router.push(backHref)}>
             {backLabel}
           </Button>
         )}

src/features/admin/pages/RolesPage.client.js

@@ -83,7 +83,6 @@ const RolesPageClient = () => {
                 <div className="flex items-center justify-end gap-2">
                     <Button
                         variant="secondary"
-                        size="sm"
                         onClick={() => openEdit(role.id)}
                         icon={PencilEdit01Icon}
                     >
@@ -92,7 +91,6 @@ const RolesPageClient = () => {
                     {!role.is_system && (
                         <Button
                             variant="danger"
-                            size="sm"
                             onClick={() => handleDelete(role)}
                             icon={Cancel01Icon}
                         >
@@ -179,7 +177,7 @@ const RolesPageHeader = () => {
                 title="Rôles"
                 description="Gérez les rôles et leurs permissions"
                 action={
-                    <Button variant="primary" size="sm" onClick={() => setModalOpen(true)}>
+                    <Button variant="primary" onClick={() => setModalOpen(true)}>
                         Nouveau rôle
                     </Button>
                 }

src/features/admin/pages/UsersPage.client.js

@@ -78,7 +78,6 @@ const UsersPageClient = () => {
             render: (user) => (
                 <Button
                     variant="secondary"
-                    size="sm"
                     onClick={() => setEditingUserId(user.id)}
                     icon={PencilEdit01Icon}
                 >