This update prepares for a change to improve how the portal communicates with the Odoo server. It now allows the server to recognize requests originating from the portal, enabling targeted limitations and better performance. This refactoring enhances the overall system's responsiveness and integration.

This update clarifies the event triggered when the website builder prepares to save a complete document. The change ensures the system correctly handles saving the entire website design, rather than individual snippets. This improves the reliability and efficiency of the website building process.

This commit renames the resource
`on_will_reset_history_after_saving_handlers` (formerly `save_handlers`) to `on_ready_to_save_document_handlers`. To convey that:
- the event is "the builder is ready to save the document"
- this is about saving the whole document (and not a custom snippet)