fix: Ensure viewport updates and consistent key handling in drawing tools

Co-authored-by: aider (gemini/gemini-2.5-pro) <aider@aider.chat>

src/RectangleTool.cpp

@@ -107,9 +107,7 @@ void RectangleTool::mousePressEvent(QMouseEvent *event)
         }
         p.SetCoord(worldPos.x(), worldPos.y(), worldPos.z());
         emit m_viewport->rectangleAdded(m_firstRectanglePoint, p);
-        m_isDefiningRectangle = false;
-        m_viewport->setProperty("widthInput", "");
-        m_viewport->setProperty("heightInput", "");
+        deactivate();
     }
 }