On summary LLM call failure, maybe_compact was returning system_msgs+recent
(dropping the older half) with was_compacted=False, misleading the caller into
thinking the list was unchanged. Return the original messages list unchanged so
no history is lost; the next trim_for_context call handles length if needed.
Fixes#2160
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
max-freddyfire