docs: record remote preview acceptance and verify example error logging

examples/userService/internal/service/user/service.go

@@ -44,7 +44,9 @@ func (s *Service) failure(ctx context.Context, err error) error {
 	default:
 		// Do not log SQL/DSN or user input; requestId correlates the failed operation.
 		s.deps.Logger.ErrorContext(ctx, "user.operationFailed", "category", "persistence")
-		return apierrors.Internal(err)
+		// HTTP access logging also sees the returned error. Keep raw driver
+		// errors out of that path because their messages may contain input.
+		return apierrors.New(500, "INTERNAL_ERROR", "internal server error")
 	}
 }
 func (s *Service) mutate(ctx context.Context, operation string, fn func(repo.UserRepository) (model.User, error)) (*types.UserResp, error) {