List sequences

Name, status, senders, and the rollup metrics (contacts, sent, reply rate) from the workspace's cached stats, served at once whatever their age. When they are more than five minutes old a refresh runs in the background and stats_refreshing is true: read the list again a few seconds later for the newer numbers. Only a workspace whose stats have never been built waits for them. stats_refreshed_at is when the numbers were computed; None only when they have never been built and could not be built on this request (for example, another request was building them). What holds a running sequence (hold, such as the tasks waiting for approval) is read live on every request, never from the cached stats, unless include_holds is false. Each sequence says whether the person asking starred it and when they last opened it: both are that person's own. favorites keeps only the sequences they starred; recent keeps only the ones they opened, the latest open first, at most 20. An API key has no person, so both read empty for it.