v0.31.2: tokens lead the Usage page; a limit on some models no longer stops the agent

• Tokens first. The Usage page opens with tokens per day, stacked by agent, from each agent's own records, so Claude
  Code work on a subscription (no per-call spend) shows day by day. Spend moves beside the daily totals, and the agent
  filter lists agents that only have token records. The daily totals use the same token numbers as the chart.
• Model-scoped limits. A limit on some of an agent's models no longer stops the whole agent: Fable's own weekly
  limit is a sub-limit of Claude's week (Claude keeps working on Opus), and when model groups split an agent
  (Antigravity's Gemini and Claude buckets) the roomiest group decides. Before this, a full Claude bucket on Antigravity
  would have held all of its work until the weekly reset.
• For agents: nothing changes.