User list-content collapsed to text (image turns keep list form), assistant
content null -> "", canonical key order, tokens/chars recomputed with
scaffold_agent.record.count. Lossless by construction: flattened record text
is byte-identical per record, so totals are unchanged (19,652 records,
1,005,069,419 tokens). Verified by an independent per-record join.
Link Scaffold Chat (formerly Scaffold-CoT); document meta/counter fields
