[ingvarch]

What changes

urga reads three things newer clusters report and showed nothing of.

• A plan shows the allocations a group will reschedule now or after a delay,
  disconnect and reconnect (Nomad 1.11), in the words and colors of the other
  counts. An evaluation shows what it planned for each group and the
  allocations it preempted, after its placement failures. An older cluster
  shows neither.
• A client with an allocation limit (node_max_allocs, Nomad 1.10.2) shows
  Allocations 3 of 10 at the top of its screen; the count is n/a until its
  allocations are read. The client list paints a full client in the attention
  color, like one that is draining or ineligible, and ! keeps it. The list
  reads in full only the clients that have a limit, and their allocations in
  one filtered request. With the event stream on, a client that fills up is
  marked within 30 seconds: Nomad streams changes of a client, not of the
  allocations placed on it, and watching allocations in every namespace would
  need a token that reads jobs everywhere.
• A client of Nomad 1.11 or later shows when its identity expires
  (Identity expires in 23h, or expired). i shows its claims, ctrl+n
  renews it after a question and is hidden in read-only mode. An older client
  is not asked, so it shows none of it.

Closes #111
Closes #112
Closes #113

Checklist

• The test for this change was written first and failed
• make check is green
• The title is a conventional commit: feat(ui): ..., fix(nomad): ...