[Help] Default show all filter form item in pro table

Default show all filter form items in the Pro Table. If the user wants to display fewer items, they can click to show less.

Start by tracing the Pro Table filter form rendering and the existing show-more/show-less behavior. Confirm how the filter item visibility is initialized, then verify that all items are shown by default and that users can still choose to show fewer items.

Written by the indexing model from the issue text.