Answer support email in Inbox

Plenty of our customers still email support instead of using the widget. Right now that's a separate tool, so we have two places to check, and email never benefits from the agent or the Library.

We'd like email to arrive in the same Inbox: the agent answers or drafts from the same knowledge, an operator can take over and hand back like a chat, and the conversation can be linked to a Case. One queue for everything.