claude@clouddev1
5410075398
The Iteration-2 rule wrote a header-only CSV for every existing table, which surprised users who created a table and saw a file appear before any data went in. Tighten the rule: a CSV exists iff the table has rows. Persistence::write_table_data now delegates to delete_table_data when the snapshot is empty, removing any prior CSV. The schema-only invariant (YAML knows the table; CSV knows its rows) is preserved. The cascade-delete integration test was rewritten to assert the CSVs vanish; two new tests pin the rule (create -> no CSV; delete --all-rows -> CSV removed). Tests: 291 passing (256 lib + 9 + 9 + 17), 0 failing, 0 skipped.