Preserve HTTP status codes in LLM history and safe telemetry

docs/telemetry-v1.md

@@ -1,5 +1,12 @@
 # Operational telemetry v1
 
+LLM round events expose numeric `http_status` for nonretryable HTTP failures and
+for every entry in `failed_providers`. Use the `events` CLI to inspect temporary
+provider failures (warning events). For example, 429 indicates a quota/rate-limit
+response; 503 indicates service unavailability. Missing status on older records,
+timeouts or connection errors means unknown, not success. Provider bodies and
+headers are never logged. This field does not change retries or case budgets.
+
 Telemetry observes existing library execution, not case truth. It never resumes
 BLOCKED cases, refills budgets, changes routing, retries a model, edits packages,
 executes tools or deletes case artifacts. `docs/architecture.md` is unchanged.