Improved the namespacing by dropping the app prefix on types, e.g.
chat-hook-action -> action. Compensated for shadowing by importing the
/sur files behind a face. End result is that a chat-hook-action becomes
an action:hook. Splits chat-json into lib/chat-{hook,store,view}. Uses
^? on changes files in /lib and /sur to discourage deeply nested
importing.
