POST /api/v1/integrations/llm-usage stores priced LLM usage events
(idempotent on gateway_request_id) in llm_usage_events. The gateway is
the LLM-pricing authority — arcadia-cloud trusts the charge it sends
rather than re-pricing.
The monthly invoice rollup now appends an llm_usage line per deployment
alongside the infra quote lines; the exact decimal charges are summed
and rounded to cents once. Closes the gateway→cloud billing loop.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Giuliano Silvestro
e1f0aedcf7