Wt

In WTreeView, clicking the expand/collapse button currently triggers row selection.
This can lead to accidental selection/deselection of items when the user merely intends to navigate the tree hierarchy.
The behavior is also inconsistent with WTree, where the expand/collapse button does not trigger row selection.
We should prevent row selection in these cases.

Root cause: The ToggleButton inside WTreeViewNode allows mouse events to bubble up to the WTreeView container. The view-level event handler onItemEvent intercepts these events and triggers the selection logic, regardless of whether the click landed on the toggle button or the item content.

Proposed fix: Modify WTreeViewNode::updateGraphics to prevent event propagation on the expansion control widgets. This ensures the event is consumed by the button and does not reach the parent view's selection handlers.