[FEAT] EventSub forwarding

[techygrrrl]

It would be great to be able to forward event sub data to URL's, on a per-event basis.

This would be similar to the Helix passthrough, but for EventSub (and the other direction).

I know this is a lot of work so I understand if it's not feasible. Also given that the cloud provider we use is having some changes to their pricing plans, if these changes impact TAU users to the point they move off the platform, this may not even be worth building if we have to run it locally.

Describe the solution you'd like

The ability to click into a part of the dashboard and enter forwarding URLs, and receive forwarded webhook events to those configured URLs.

Please see attached PDF for a tech spec of a possible solution. It includes a proposed flow including auth/verification.

Feature_EventSub_forwarding.pdf