A user prompt could render at the very bottom of a conversation, below the
assistant turn that had already answered it.
merge_session_messages_append_only reconciles the sidecar with state.db. When a
state.db row carries a typed row id that is unique to state.db and absent from
the sidecar (the two stores do not share an id space),
row_id_preserves_source_multiplicity is true and the row bypasses the
sidecar-timestamp-range block -- including the
_insert_state_message_chronologically call that block owns. It then fell through
to the terminal merged_messages.append and landed at the tail regardless of its
timestamp.
The full display path re-sorts by timestamp afterwards
(_merged_webui_lineage_messages_for_display), which hid the defect. The
paginated path used for the initial render (msg_limit) does not, so the user saw
their own message below its own answer until a full reload reshuffled it.
Place such a row in its chronological slot when its timestamp predates the
sidecar tail, falling back to append when no safe slot exists. Rows that are
genuinely newest still append at the tail, so the append-only contract (never
drop a local row) is preserved.
Verified on the reported transcript: the merged tail now ends on the assistant
conclusion instead of the orphaned prompt, with the same message count.
Anthony Ruiz
2153846bb1