The chat column is more expensive than it should be right now. In particular:
- Loading a conversation //or// receiving a message causes `/conpherence/` and `/notification/` updates.
- We should just ship counts back on the response.
- The column view itself looks has some awkward semantics around Remarkup rendering (multiple redundant fetches for `@mentions`, for example).
- The column looks like it's building the "Calendar" and "Files" tabs even though they are not reachable.