The v2 backup silently dropped the entire rulebook system (rulebooks, topics,
rules), the project subscription/suppression join tables, and events — so a
'full' backup wasn't. v3 adds all of them with FK re-mapping on restore, and a
_not_included field that names the still-deferred tables (ACL groups/shares,
api_keys, embeddings, transient/operational) so the gap is explicit, not silent.
restore_full_backup routes v2 and v3 through one path; v3-only sections are
guarded by data.get so a v2 payload still restores cleanly.
Tests: version/coverage constants, pure join-table row helpers, and the export
contract via a mocked session (CI has no DB; full round-trip is a manual check).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
