Add snackbar feedback

web/src/components/admin/permissions/PermissionsTab.tsx

@@ -99,6 +99,10 @@ const PermissionsTab: React.FC = () => {
             setPermissions(prev => prev.map(item =>
                 item.id === p.id ? { ...item, is_default: !item.is_default } : item
             ));
+            showNotification(
+                p.is_default ? 'Removed from default' : 'Set as default',
+                'success',
+            );
         }
         setTogglingDefaultId(null);
     };

web/src/components/admin/users/UserDetailDialog.tsx

@@ -122,11 +122,17 @@ const UserDetailDialog: React.FC<UserDetailDialogProps> = ({
         if (checked) {
             const res = await adminService.addUserPermission(user.id, perm.id);
             if (res.error) { showNotification(res.error, 'error'); }
-            else { setUserPerms(prev => new Set([...prev, perm.id])); }
+            else {
+                setUserPerms(prev => new Set([...prev, perm.id]));
+                showNotification(`Permission granted: ${perm.permission_name}`, 'success');
+            }
         } else {
             const res = await adminService.removeUserPermission(user.id, perm.id);
             if (res.error) { showNotification(res.error, 'error'); }
-            else { setUserPerms(prev => { const s = new Set(prev); s.delete(perm.id); return s; }); }
+            else {
+                setUserPerms(prev => { const s = new Set(prev); s.delete(perm.id); return s; });
+                showNotification(`Permission revoked: ${perm.permission_name}`, 'success');
+            }
         }
         setTogglingPermIds(prev => { const s = new Set(prev); s.delete(perm.id); return s; });
     };