[FR] Add support for incoming email for plugins

[matmair]

Please verify that this feature request has NOT been suggested before.

• [X] I checked and didn't find a similar feature request

Problem statement

Plugins do not have a way to receive responses to emails that they have sent

Suggested solution

Add django-anymail to receive mails from various ESPs https://anymail.dev/en/stable/inbound/

Describe alternatives you've considered

I currently use an IMAP library to check periodically but it would be nicer to handle this in core.

Examples of other systems

A lot of PLM systems support emails

Do you want to develop this?

• [X] I want to develop this.

[matmair]

Note: The proposed library would not support normal IMAP/POP. https://django-mailbox.readthedocs.io/en/latest/index.html would do that but API-based mail delivery has proven way more reliably in my deployments.

[SchrodingersGat]

@matmair for my own curiosity - in what context might you expect a plugin to receive an email? And do what with it?

[matmair]

Delivery notices for example.

[github-actions[bot]]

This issue seems stale. Please react to show this is still important.

[matmair]

Still important but a lot of open half-finished PRs from right now so pushing back