backend env updates and brand json files

.env.example

@@ -144,6 +144,19 @@ DB_NAME=pgvector
 DB_USER=postgres
 DB_PASSWORD=changeme
 
+# How often (seconds) to reconcile brand_* tables against data/seed_catalogs/.
+#
+# Brands are discovered from the database, not from a list: every brand_* table
+# is enumerated on each request, so a new one shows up in the catalog with no
+# registration step. This interval covers the other direction - mirroring a
+# table created directly in the database into a seed catalog file - which
+# otherwise only happens at startup or via POST /api/system/brand-sync.
+#
+# A sweep with nothing to do is one COUNT(*) per brand table and writes nothing.
+# Raise it if the database is remote and the chatter matters; 0 turns the loop
+# off entirely, leaving only the startup run and the manual endpoint.
+BRAND_SYNC_INTERVAL_SECONDS=300
+
 USE_S3=true
 S3_ACCESS_KEY=your-do-spaces-key
 S3_SECRET_KEY=your-do-spaces-secret