Add toggle to quickly show the "before" of a LTN

When doing a presentation it would be useful to be able to quickly show the current state, before any restrictions.

I tried to create a new neighborhood with the same limits in the same project, but the restrictions are already applied to it.

I guess creating a different project would work, but it's not convenient to switch from one to the other.

在前端代码中查找处理切换或状态可见性的 UI 组件。此功能可能涉及添加一个按钮或开关，以便在当前的受限视图和原始的“before”状态之间切换。检查邻域数据和限制条件是如何加载及应用的。先探索演示模式或视图控件，以了解应在哪里集成此切换功能。

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