- Assembly instaiated operations

- assembly forward proagation

src/fluency/ui/technical_drawing_widget.py

@@ -417,19 +417,15 @@ class TechnicalDrawingWidget(QWidget):
         self._kernel = kernel
 
     def set_active_component(self, component) -> None:
-        """Use the given component as the drawing source and regenerate."""
+        """Use the given component as the drawing source."""
         self._active_source_kind = "component"
         self._active_source_id = component.id
-        self._on_generate()
 
     def set_active_assembly(self, assembly) -> None:
-        """Use the given assembly as the drawing source and regenerate.
-
-        The assembly is treated as a single fused part (all bodies merged).
-        """
+        """Use the given assembly as the drawing source."""
         self._active_source_kind = "assembly"
         self._active_source_id = assembly.id
-        self._on_generate()
+
 
     def generate(self) -> None:
         """Public entry point: generate for the current source."""