## What changed
- Make `thread/turns/list`, `thread/items/list`, and `thread/revert` available
without the experimental API capability.
- Stabilize `thread/reverted`, `thread.historyMode`, and the pagination fields
used by `thread/resume` and `thread/fork`.
- Publish the promoted requests, responses, and fields in the stable JSON and
TypeScript schemas, and update the app-server documentation accordingly.
GitOrigin-RevId: 18b8c53c265211597bb1a62fd62f66f4a3df5f06
To improve performance of UI loads from the app, add two main
improvements:
1. The `thread/list` api now gets a `sortDirection` request field and a
`backwardsCursor` to the response, which lets you paginate forwards and
backwards from a window. This lets you fetch the first few items to
display immediately while you paginate to fill in history, then can
paginate "backwards" on future loads to catch up with any changes since
the last UI load without a full reload of the entire data set.
2. Added a new `thread/turns/list` api which also has sortDirection and
backwardsCursor for the same behavior as `thread/list`, allowing you the
same small-fetch for immediate display followed by background fill-in
and resync catchup.
