Spec §"Behavior contract" line 74 says `id:` is captured into
`metadata.user_id_alias` only. Remove the redundant `user.insert`
that was also writing it into the user map, and update the snapshot
baseline accordingly.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Two markdown fixtures with hand-authored JSON baselines that pin the
§0 Q9 derive output across runs:
- frontmatter-only.md exercises the YAML happy path with most fields,
unknown keys, an `id:` field, and a non-UTC created_at (so the
baseline shows original_timestamps preservation).
- mixed-lang.md is body-only with no `lang:` field; baseline pins the
lingua autodetect result for our enabled language set.
A separate `emit_snapshots` test (marked `#[ignore]`) regenerates the
baselines from the current parser output. A determinism test parses
the fixture twice and asserts equality so any non-determinism (e.g.
key ordering, lingua nondeterminism) fails fast.
