Uses actions/ai-inference with GPT-5 to classify newly opened issues
and pull requests against the area/*, integration/*, db/*, and
concern/* label namespaces.
The system prompt is rendered at runtime from the live repo label list
plus descriptions, so GitHub label state is the single source of truth
for the taxonomy. Suggested labels are re-validated against the live
list before being applied, capped at 6 per item.