Overview
Complementing T331: Better cross-post management, this will make platform/channel connections more useful and enable quick sharing to them.
Implementation
The API should simply supply a crosspost endpoint for sending the exact same crosspost object that would be passed with a new post, which simply fetches the post information and processes it and sends it off as if it were a newly published post.
Design
Posts list should include an action under each post that says "Share" or similar. Pressing it should present a dialog with the cross-post options normally in the Pad dropdown.
We could do things here like preview what a post looks like on each post (a la Blogger posting to Google+), showing different data sent to each platform, what the tweet might look like, etc.