Found proactively by deepening the round-trip test from node-TYPE survival to
ATTRIBUTE fidelity (distinctive attr values per node). Two real losses (the
other 3 candidates — mathInline/mathBlock/pageEmbed — were verified to be
correct; the probe had used wrong attr names):
- subpages `recursive`: the converter emitted a bare div and the schema mirror
didn't model the attr, so a recursive subpages reverted to non-recursive on a
round trip. Now emits `data-recursive="true"` and the mirror parses it back
(matching @docmost/editor-ext).
- details `open`: the `open` (collapsed/expanded) state lives on the details
node, but the converter emitted the `<details>` wrapper from the summary case
without it, so the state was dropped. The wrapper now carries `open`.
The round-trip test now also asserts attribute fidelity (12 cases) so these are
locked. Schema-surface snapshot updated for the new subpages attr.
git-sync vitest 671 (+1 expected-fail), §13.1 gate 27.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
ad2b7a71bc