Remote object access

[evanp]

"As an ActivityPub client developer, I want a reliable method for accessing objects on remote servers with the user's authorization, so I can read private or followers-only data."

[evanp]

We have the proxyUrl endpoint for this, but it's also possible to have some kind of shared client key, maybe using the keys endpoints, and then using HTTP Signature for the request. Worth a discussion, at least!