Addresses @helix4u's review on #91493:
- conversation_loop now stamps failure_retryable (the real ClassifiedError
verdict) next to failure_reason; error_surface prefers it and only falls
back to the reason set for older results. Fallback set corrected to match
classify_api_error (auth, format_error, billing_unverified now
non-retryable).
- The descriptor carries the failing session's provider/model captured at
classification time; Copy error details prefers them over the foreground
composer atoms.
- Open logs is labeled 'Open Desktop logs' on remote/cloud connections —
the local folder holds transport logs, not the remote runtime's.
- API-exception module allowlist widened to botocore/boto3/google/grpc/
requests/aiohttp so other adapter SDKs don't misclassify as gateway.
334bcbac93