Send data chunk by chunk to user interface

- [ ] Edit backend to send data chunk by chunk but optioanl.
- [ ] In app by default requrest data in chunk by chunk if error fall back to complete

Start by locating the backend request path and the app code that requests data; the issue names no files or tests. Confirm how optional chunked responses and fallback behavior should be represented, then verify that the app uses chunked requests by default and still receives complete data when chunking fails.

Written by the indexing model from the issue text.