feat: move to lazy widget import

tests/unit_tests/test_rpc_widget_handler.py

@@ -1,7 +1,6 @@
 from unittest.mock import patch
 
-from bec_widgets.utils.bec_widget import BECWidget
-from bec_widgets.utils.plugin_utils import BECClassContainer, BECClassInfo
+from bec_widgets.utils import plugin_utils
 from bec_widgets.utils.rpc_widget_handler import RPCWidgetHandler
 
 
@@ -10,21 +9,22 @@ def test_rpc_widget_handler():
     assert "Image" in handler.widget_classes
     assert "RingProgressBar" in handler.widget_classes
     assert "BECDockArea" in handler.widget_classes
-
-
-class _TestPluginWidget(BECWidget): ...
+    assert isinstance(handler.widget_classes["Image"], tuple)
 
 
 @patch(
-    "bec_widgets.utils.rpc_widget_handler.get_all_plugin_widgets",
-    return_value=BECClassContainer(
-        [
-            BECClassInfo(name="DeviceComboBox", obj=_TestPluginWidget, module="", file=""),
-            BECClassInfo(name="NewPluginWidget", obj=_TestPluginWidget, module="", file=""),
-        ]
-    ),
+    "bec_widgets.utils.bec_plugin_helper.get_plugin_rpc_widget_registry",
+    return_value={
+        "Image": ("plugin.module", "PluginImage"),
+        "NewPluginWidget": ("plugin.module", "NewPluginWidget"),
+    },
 )
 def test_duplicate_plugins_not_allowed(_):
-    handler = RPCWidgetHandler()
-    assert handler.widget_classes["DeviceComboBox"] is not _TestPluginWidget
-    assert handler.widget_classes["NewPluginWidget"] is _TestPluginWidget
+    plugin_utils.rpc_widget_registry.cache_clear()
+
+    try:
+        handler = RPCWidgetHandler()
+        assert handler.widget_classes["Image"] != ("plugin.module", "PluginImage")
+        assert handler.widget_classes["NewPluginWidget"] == ("plugin.module", "NewPluginWidget")
+    finally:
+        plugin_utils.rpc_widget_registry.cache_clear()