fix(catalog): filter vehicle-brands to North America OEM brands only

/vehicle-brands now uses get_brands_for_mode('oem') to return the same
36 North American brands (Mexico/USA/Canada) as the regular catalog flow,
instead of all 619 brands in the database.

pos/blueprints/catalog_bp.py

@@ -598,19 +598,23 @@ def _match_vin_to_catalog(master_conn, vin_info):
 @catalog_bp.route('/vehicle-brands', methods=['GET'])
 @require_auth('catalog.view')
 def vehicle_brands():
-    """Return vehicle brands for brand-first catalog browsing.
+    """Return North American vehicle brands for brand-first catalog browsing.
     
-    Returns all brands from the brands table (fast) rather than scanning
+    Uses the same OEM_BRANDS_NA filter as the regular catalog so that
-    the 256M-row part_vehicle_preview materialized view.
+    the brand list is consistent across both navigation modes.
     """
+    from services.catalog_modes import get_brands_for_mode
+    allowed = list(get_brands_for_mode('oem'))
+
     def _query(master):
         cur = master.cursor()
         try:
             cur.execute("""
                 SELECT id_brand, name_brand
                 FROM brands
+                WHERE name_brand = ANY(%s)
                 ORDER BY name_brand ASC
-            """)
+            """, (allowed,))
             rows = cur.fetchall()
             return jsonify({
                 'brands': [