- Add enable_deduplication and show_deduplication_step config options
- Rename hash_file step to check_for_duplicates
- Make deduplication step conditional based on configuration
- Add is_duplicate and duplicate_of_id fields to FileRecord model
- Create database migration for new deduplication fields
- Update process_document task to log deduplication results
- Update step visualization to show/hide step based on config
- Update status calculations to include deduplication step conditionally
- Default: deduplication enabled, step displayed
- Can be configured to hide from UI while still processing