This draft change updates how several Odoo apps handle real-time notifications and related communication workflows. It may improve responsiveness for IoT delivery devices, mail, follow-ups, and VoIP interactions, though the work appears preliminary based on the draft title and commit messages.

The signing flow now loads saved signatures, initials, and font choices more efficiently, reducing repeated server calls when users open signing fields. This should make document signing feel faster and smoother, especially for documents with many required signatures or initials.

When a signature or initial is required in sign, a RPC call is done to route
`get_signature`. This is bad for performance since we need to be doing HTTP
calls everytime a wizard is opened. This commit removes the get_signature
route and now signatures are inserted in `get_document_qweb_context` as an
`auto_value` key in the sign_item_types dictionary. Also, `auto_field` keys
were replaced by `auto_value` to prevent confusion between the `auto_field`
field and the value that should be auto-filled in the document.

task-2735814