- tech drawing and render improv

src/fluency/ui/technical_drawing_widget.py

@@ -421,6 +421,15 @@ class TechnicalDrawingWidget(QWidget):
         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).
+        """
+        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."""
         self._on_generate()