The sweep / walk-forward / mc family-member stdout lines routed the embedded
RunReport through serde_json::json! -> a serde_json::Value, which re-alphabetizes
the manifest keys (broker-first) and, for mc, even reordered the top-level keys
(seed after report). That diverged from the commit-first declaration order that
RunReport::to_json and the stored families.jsonl already use.
Splice the pre-serialized report into a hand-built line via family_member_line /
mc_member_line so each family-member stdout line is byte-identical to its
families.jsonl record (commit-first manifest, seed between family_id and report).
RED-first: the two new key-order tests fail against the old json! helpers and pass
after the format! rewrite.
closes#99
Brummel
094d63bc47