TreeTable: scrollHeight="flex"

Describe the feature you would like to see added

Currently TreeTable does not support scrollHeight="flex" as DataTable does.

Is your feature request related to a problem?

When scrollHeight="100%" is used, .p-treetable-scrollable-body max-height is computed dynamically during the render, which causes problems, when you need to change TreeTable height without re-render (e.g. by putting it in a vertical splitter or adding other items in a flex column). DataTables don't have this problem when scrollHeight="flex" is used.

Since the height of the TreeTable is determined by the max-height property, it doesn't fill the available space of the parent container when there are just a few rows in the table and when a horizontal scroll is needed, the scrollbar appears right below the last row instead of the bottom of the parent container.

Reproducer

https://codesandbox.io/p/sandbox/primereact-demo-forked-zprg8k

Start with the linked CodeSandbox reproducer and compare TreeTable's scroll behavior with DataTable's existing scrollHeight="flex" support. Trace how .p-treetable-scrollable-body handles height and max-height, then verify that resizing the parent or changing sibling content updates the table height and keeps a horizontal scrollbar at the container bottom.