- Rename /curate/retag to /curate/swap; response now includes new_tag
- /curate/reorder: read body["order"] key (was ordered_ids); include date field
- /curate/remove and /curate/swap: return 404 if asset_id not found
- Update phase3.html JS fetch calls and reorder payload to match spec
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>