pub fn check_json(doc: &Doc) -> WriteReportExpand description
Report what writing JSON would adjust, without producing output.
Walks every leaf via the shared crate::formats::visit_grouped walker
(issue #51) rather than a bespoke collect_leaves pass; the path
String that ends up in a crate::report::Adjustment is only built
for the (rare) NaN/Infinity leaf – not for every leaf up front (issue
#44), since visit_grouped reuses one path buffer for the whole walk.