SearchKit - Keep randomly sorted results stable across pages

SearchKit - Keep randomly sorted results stable across pages

SearchKit allows ORDER BY RAND() but this can cause unexpected reshuffling
when using the pager, editing-in-place or bulk-updating records.

The solution is to generate a seed on the client-side when the display initializes,
and re-use it every time results are fetched. This keeps the order stable,
only reshuffling when the browser reloads the page.