Improving Row Pinning behavior with manual Server-Side pagination #6006

Hi,

The current row pinning feature works great if used with a client-side pagination but it seems quite limited when using a server-side pagination.

e.g.

1. The user is at the first page and pin the third rows. Tanstack table's rowPinning state will the keep the index of that row. The index is 2.
2. The user go to the next page of the table. A new call is make to the server and new data are loaded.
3. A row is still pinned but it does not contains the data that have been previously pinned. It's now containing the data of new call to the server at the same index.

Proposal
In a very naive way, I think tanstack should keep track of the whole row's data instead of just the index. I think, it could be flexible to save pinned row in local storage and ensure the correct data are displayed.

Thanks