

### Fixed
- **Explicit GC after each validation chunk**: rdflib `Graph` objects have internal circular references that Python's cyclic GC may not reclaim promptly during tight loops. Even with a fresh `NeatSession` per chunk, unreleased `Graph` objects from prior chunks accumulate in memory until OOM. Fixed by explicitly `del neat, report_graph` and calling `gc.collect()` after violations are extracted in both `instance_sync_cursor_validation.py` and `partitioned_validation.py`.