Detect very short oneways that create illegal ratruns

When studying a new circulation plan, in addition to detecting illegal configurations [https://github.com/a-b-street/ltn/issues/324], it would be great to detect very short (< 50m ?) oneways that may be taken illegally.

There's one here : https://a-b-street.github.io/ltn/?project=b4bb49da-126e-477a-8f94-f976261388b8#18.43/43.6006746/3.8931434

(small section of "rue des 7 cans" that allow to take "avenue du petit train")

该 issue 提到检测会造成非法抄近路的超短单行道（< 50m）。首先检查处理道路网络分析和非法配置检测的代码（可能由 issue #324 引用）。查找计算道路长度、识别单行道以及分析连通性以发现潜在非法抄近路的模块。目标是在流通计划分析中添加一条新的检测规则，用于标记这些超短单行道。

由索引模型根据 Issue 内容生成。