Replace the separate panel_usage SSE event + frontend accumulator with
server-side seeding of the worker's usage object. Both the done-event and
FinalizeChain read from the same usage, so panel (Fusion/MoA) member tokens
now flow into the live badge AND the DB as a single source of truth — the
badge no longer drops to the worker-only value after F5.
- RunPanel takes a TokenUsage usageSink; accumulates member costs after the
Task.WhenAll barrier (single-threaded, no lock)
- ChatEndpoint passes panelUsage as seedUsage to all three worker paths
- StreamChat / StreamChatViaCli / OpenAI StreamChat fold seedUsage into usage
at creation time, so every exit path persists it
- OpenAI done-events extended with cacheCreation/cacheRead fields for live
consistency when seeded by Anthropic members
- chat.js: remove redundant _panelUsage / _addPanelUsage / panel_usage
- TODO.md: mark the live-only v1 boundary closed, note the new mechanism
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
