Add dev-prod harmonize tool for bidirectional catalog and image sync.

Schema migrates dev to prod only; catalog rows merge by updated_at and images by mtime with union merge and conflict reporting.

Co-authored-by: Cursor <cursoragent@cursor.com>

Documentation/Plans.md

@@ -3,7 +3,7 @@ this file contains draft for future releases and features
 1. Multy language support, russian version at least, search for best implementation, preferably story in db and easily expandable. tool to check and correct translation
 2. tool to manage links (influence/influenced by ) import csv's ( define format), edit ,add, delete, visualize, map to pictures/ entities
 3. tool to monitor/manage (plan actions) of curator actions, markers to check painting/text ?
-4. tool to sync prod /env resources (both ways), db structure, db data, images, users etc
+4. ~~tool to sync prod /env resources (both ways), db structure, db data, images, users etc~~ — done for catalog DB + images: `npm run harmonize` (schema dev→prod only; users/audit excluded) — [harmonize-dev-prod.md](harmonize-dev-prod.md)
 5. curator_audit_log should contain log of actions like fixit, checked, upload etc with details for which entity it was made and details what was the action and outcome
 6. ~~create search by entity (painting, artist, movement)~~ — done: timeline header + `GET /api/search`
 7. create guided tours (with text/extra infor, set of entities)