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>

scripts/migrate-sync-timestamps.js

@@ -0,0 +1,17 @@
+require('dotenv').config();
+const fs = require('fs');
+const path = require('path');
+const pool = require('../server/db');
+
+async function main() {
+  const sqlPath = path.join(__dirname, '../db/migrate-sync-timestamps.sql');
+  const sql = fs.readFileSync(sqlPath, 'utf8');
+  await pool.query(sql);
+  console.log('Catalog sync timestamps ready (updated_at + triggers)');
+  await pool.end();
+}
+
+main().catch((err) => {
+  console.error(err);
+  process.exit(1);
+});