def migrate(cr, version):
    """Best-effort Odoo 17 -> 18 port marker. No destructive schema changes."""
    if version is None:
        return
    # Drop obsolete view xmlids that inherited removed website_sale_product_configurator templates.
    cr.execute("""
        DELETE FROM ir_ui_view
        WHERE id IN (
            SELECT res_id FROM ir_model_data
            WHERE module = 'theme_prime'
              AND name IN ('configure_optional_products', 'optional_product_items')
              AND model = 'ir.ui.view'
        )
    """)
    cr.execute("""
        DELETE FROM ir_model_data
        WHERE module = 'theme_prime'
          AND name IN ('configure_optional_products', 'optional_product_items')
          AND model = 'ir.ui.view'
    """)