* Add `GET /capabilities` to Plugins API
It aims to:
- help the client verify the data-domain the token is associated with
- list all the features available for the site's owner
(and therefore determine availability of the subset of those for the current
Plugins API caller)
The endpoint does not require authentication, in the sense that it'll
always respond with 200 OK. However when the token is provided,
a verification lookup is made.
* Remove IO.inspect() call
* Credo
* Aesthetics
* s/send_resp/send_error/
* Call preload just once
hq1