When styling a theme in XML, we don't have access to the top of `.o_layout`, leading to the design element being located in different places depending on whether it's been added programmatically or in XML. This harmonizes it, ensuring it's always at the top of `.o_layout`. X-original-commit: ab61f1d38b2852ec0b6727122a1cfc2cd81cfc9f Part-of: odoo/odoo#92138