Feature Request: Signing with third-party tools

[Snuffsis]

Feature Title

Third-party signing

Feature Description

I am proposing a feature where it would be possible to enable signing with third-party Electronic Trust Service Providers.
This would be for making it possible to get stronger assurances that the person that side the document is the person it was meant for. As right now, if the url to the document is leaked it can be signed by anyone (unless I have missed something).

What type of feature are you requesting?

3rd party integration

Importance

Medium

Additional Context

One popular tool for this in my region is Scrive, which has integrations with our nation-wide identity service called "Bankid" (and a few others) that guarantees that the person that signed the document is the person in question.

This tool is used by landlords, existing contract managing tools etc that can't be self-hosted, to sign documents legally.

The example mentioned above does have an API, so it would be possible to integrate with it. But it would of course require that companies that want to use this feature have their own contracts with the provider and set it up with an api-key or other method.

Code of Conduct

• I agree to follow this project's Code of Conduct
• I have searched the existing issues & discussions to make sure that this is not a duplicate.