fix: Enable line tool functionality

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

src/ViewportWidget.cpp

@@ -10,6 +10,7 @@
 #include "SketchObject.h"
 #include "ApplicationController.h"
 #include "RectangleTool.h"
+#include "LineTool.h"
 #include <QMouseEvent>
 #include <QKeyEvent>
 #include <QWheelEvent>
@@ -58,6 +59,7 @@ ViewportWidget::ViewportWidget(QWidget *parent)
 
     m_cursorRenderer = new QSvgRenderer(QString(":/icons/cursor.svg"), this);
 
+    m_sketchTools.insert(static_cast<int>(ApplicationController::ToolType::Line), new LineTool(this));
     m_sketchTools.insert(static_cast<int>(ApplicationController::ToolType::Rectangle), new RectangleTool(this));
 }