Dispatch datastar-fetch events from the element that creates them

[gazpachoking]

Feature Request

The ergonomics of using datastar-fetch events would be improved quite a bit by dispatching them from the element where they are created. Currently you have to do a check in any handler for the event that evt.detail.el == el to filter instead of using the standard event bubbling of the html spec.

This was done previously in #761, but was later reverted due to #802, where streams would stop working after the element that initiated them was removed from the page. This should no longer be a concern though, as it will be a feature that the stream is cancelled when the element is removed rather than a bug starting in RC.6.

Datastar Version

v1.0.0-RC.5

[bencroker]

We’re using mutation observer, which reports when the element has been removed from the parent’s childList. At that point, el is detached but still alive in memory. So while this may be possible, we’d have to be careful to ensure that there aren’t any ramifications. For that reason, we can visit after RC.6 is out.

[gazpachoking]

Sounds good. A couple other situations that might cause issues: User is using their own abort controller. One of the elements ancestors get removed from the dom.
Ideally it would fall back to dispatching from the document. I'll do some testing once rc6 is out.