The google.genai.errors.ClientError with code 499 (CANCELLED) indicates the
client disconnected, not a server-side failure. Previously this fell through
to the generic ClientError handler and was classified as LLMServerError,
causing false 500s in Datadog error tracking.
- Add explicit 499 handling in handle_llm_error: log at info level, return
LLMConnectionError instead of LLMServerError
- Catch 499 during stream iteration in stream_async and end gracefully
instead of propagating the error
Datadog: https://us5.datadoghq.com/error-tracking/issue/c8453aaa-d559-11f0-81c6-da7ad0900000🤖 Generated with [Letta Code](https://letta.com)
Co-authored-by: Letta <noreply@letta.com>