feat: Add email open/read indication to email conversations

[dohomi]

Is your feature or enhancement related to a problem? Please describe.

Currently the user only see a check tick if an email is successfully sent to a client. It would be great if the opening state would be tracked and displayed as well, in a similar fashion like messaging with a chat widget.

Describe the solution you'd like

Show opening/read state of an email

Describe alternatives you've considered

Alternatively provide a webhook endpoint to set the state of a message. This could be done via webhook triggers of senders like Postmark or Mailgun to provide the state of a message back to the backend of Chatwoot conversation.

Additional context

No response

[linear[bot]]

CW-4506 Add email opened indication additionally to email conversations