Eric Traut f988a5f0da Preserve inherited previews for paginated thread forks (#60559) ...

## Why

Reference-backed forks can lack a local opening user message, causing them to disappear from thread listings or lose their inherited preview when a new turn is written. Compaction can also remove the opening message from the model context used to prepare a fork.

## What changed

- Persist inherited previews and preserve them when recording new turns and merging thread-list metadata.
- Include reference-backed forks with inherited history in thread listings before their first local message.
- Recover opening previews from transcript history within the requested fork boundary when compaction omits them from model context.
- Use the shared `user_message_preview` helper when deriving previews from rollout items.

## Testing

Extend thread-fork integration tests to check previews in listings before and after a new turn, after reopening, and when forking at a boundary after compaction.

GitOrigin-RevId: 5962cf71ea7104f07c9013cc77259b105e4c60d7

2026-11-10 08:52:02 +00:00

..

src

Preserve inherited previews for paginated thread forks (#60559)

2026-11-10 08:52:02 +00:00

BUILD.bazel

Extract rollout into its own crate (#15548)

2026-03-24 18:10:53 -07:00

Cargo.toml

Search compressed rollouts concurrently (#55652)

2026-10-20 18:40:33 +00:00