GET /api/v1/admin/usage: requirePlatformAdmin, service-role aggregation
queries (messages count, ai_invocations count + tokens + cost_cents,
conversations count) by tenant + daily series for last 7/30/90 days.
UI:
- Range selector (7d/30d/90d) + optional tenant filter
- UsageCharts: 3 daily-series charts (messages, AI tokens, AI cost in
BRL) via recharts
- UsageTable: per-tenant ranking by AI cost desc with messages/convs/
tokens/cost — CSV export client-side via Blob download
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
