The new `sync/relations.rs` ports the relations handler's
`get_bundled_aggregations`: thread summaries with participation and
ignored users' replies subtracted, references, and the latest edit. The
Rust sync handler bundles them for limited and newly joined timelines,
loads the redactions of the bundled events, and the encoder serializes
them. Python no longer bundles the rooms Rust computes, and the room
entries hand Python the bundles only when something reads the timeline.
A thread whose latest reply is from an ignored user falls back to
Python for that room: finding the latest reply that is not takes the
relations pagination, which is not ported.
The relations queries read the database each time. Python's relations
caches are not mirrored.
Shadow mode now compares the Rust bundles with Python's, in the encoded
rooms.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01R5b7Ruy4cgt27Mjq6Ptxbb
