Root-level testing guide: prerequisites (Node 20+, system git, .env), the offline
test suite + coverage, the §11 round-trip idempotency harness (--fixture/--corpus/
--page), and live testing against a real Docmost — read-only pull, dry-run push
(plan only) vs --apply (writes), vault git inspection, what's implemented vs not,
safety/recovery (Trash is reversible, conflicts never reach Docmost), and a
troubleshooting table.
