Interactive tree visualization renders a hierarchical family dataset from `treeData`. Nodes are SVG groups containing a colored rectangle and text label, connected by horizontal links. Clicking a node collapses or expands its children, triggering `transition` animations that reposition descendant nodes and labels. The visualization uses `d3.hierarchy`, `treeLayout`, and `linkHorizontal` to compute the tree layout, and a custom `zoom` event for panning and scaling the SVG canvas.