What changed, and when.

Added `stream_options.include_usage` field to Chat Completions. Token counts now stream in the final chunk.

Usage graphs now render at day-granularity for date ranges over 7 days. Previous behavior was always hour-granularity.

Invoice PDFs now include line-item model breakdown. Previously invoices showed a single total.

LoRA adapter export now supports GGUF format in addition to HuggingFace safetensors. Download from the console after training completes.

Audit log now filterable by actor (API key, user, system). Exported CSV includes actor field.

Rate limit headers now included on all responses: `X-RateLimit-Limit`, `X-RateLimit-Remaining`, `X-RateLimit-Reset`.