Fix direct param not updated by optimizer

src/core/factories.py

@@ -274,12 +274,16 @@ def optim_factory(optim_names, models, C):
         optims = []
         for name, model in zip(name_list, models):
             param_groups = [{'params': module.parameters(), 'name': module_name} for module_name, module in model.named_children()]
+            if next(model.parameters(recurse=False), None) is not None:
+                param_groups.append({'params': model.parameters(recurse=False), 'name': '_direct'})
             optims.append(single_optim_factory(name, param_groups, C))
         return DuckOptimizer(*optims)
     else:
         return single_optim_factory(
             optim_names, 
-            [{'params': module.parameters(), 'name': module_name} for module_name, module in models.named_children()], 
+            [{'params': module.parameters(), 'name': module_name} for module_name, module in models.named_children()] + 
+            ([{'params': models.parameters(recurse=False), 'name': '_direct'}] 
+            if next(models.parameters(recurse=False), None) is not None else []), 
             C
         )