gRPC Error Details

Rich error information attached to gRPC status using google.rpc.Status — includes structured error info, retry info, debug info, field violations, quota failures, and localized messages. Error details are serialized as protobuf Any messages and transmitted in the grpc-status-details-bin trailer header. They allow API servers to return machine-readable error context beyond the 17 status codes, analogous to HTTP Problem Details (RFC 7807).