#65919 persists verification candidates (finish_reason=verification_required
/ verify_hook_continue) to state.db but collapses them out of the in-memory
model history via repair_message_sequence. The eager session.resume + REST
paths read the verbatim display lineage (candidate present), but the
warm/live-reuse payload (_live_session_payload) built its user-visible
messages from the collapsed in-memory model history — so switching to a
still-live session dropped the substantive verification answer that a cold
resume of the SAME session showed. That divergence is the cross-session
"substantive text vanishes on switch" class, and the direct sibling of the
resume-duplication regression fixed in #68149.
Reconcile the persisted display lineage (candidate-inclusive, the same
get_messages_as_conversation(..., include_ancestors=True) read the eager
resume + REST paths use) with the fresh in-memory tail in
_live_visible_history, so all three surfaces agree by construction while a
not-yet-flushed live turn is still shown. Extracted
_reconcile_display_with_live as a pure, DI-testable function (anchors on the
last persisted row's (role, text); appends only the uncovered in-memory tail;
trusts the DB display when the tail can't be anchored).
Tests: unit coverage for candidate-inclusion, freshness, empty/raising-DB
fallback, and the combined candidate+fresh-tail case. The existing freshness
guard (test_session_resume_live_payload_uses_current_history_with_ancestors)
stays green.
Brooklyn Nicholson
850b8da332