feat: Prevent Tab key from moving focus outside active viewport tools

src/ViewportWidget.h

@@ -58,6 +58,7 @@ protected:
     void mouseMoveEvent(QMouseEvent *event) override;
     void wheelEvent(QWheelEvent *event) override;
     void keyPressEvent(QKeyEvent *event) override;
+    bool focusNextPrevChild(bool next) override;
 
 private:
     void initShaders();