One quiet row beneath the composer/question shell (not flush to the
screen bottom; static height, outside the morphing shell):
- LEFT: context window + session cost, clickable → per-turn detail
popover (context, total, unpriced count, one row per turn with
model/steps/cost). All folds from core/prices.ts — sessionCost,
contextWindow, turnCost — no cost math in components.
- RIGHT: model + "Thinking —" — a placeholder slot for the coming
model/thinking-level CONTROL (later work with its contract changes);
display-only today, model read from the last turn's usage,
pretty-printed (Glm 5.3 Flash).
- Data: the record's turns log, seeded on mount, refreshed when the
local stream settles, kept fresh by the existing record re-syncs.
No turns yet → "—" everywhere; unpriceable turns never fold into a
fake $0 (the doctrine).
- formatUsd/formatTokens moved to components/usage-format.ts (shared
with the activity dock); prettyModel joins them, pure + tested.
