[Minor] Independent SHP Vehicle Turret Files

[Fly-Star-him]

SHP turret vehicles support the use of *tur.shp files.
SHP炮塔车辆支持使用*tur.shp文件。

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[DeathFishAtEase]

I believe that even without any additional flags, it should be documented in detail as an Improvement. For instance, for Shape vehicles that use *tur.shp, what sequence should be used for the shp files that act as the body, what are the advantages of the new approach, how to transition from the old usage to the new usage, and other such details, similar to how it's done for Stationary vehicles.

我想它即便没有任何新增语句也应当作为一个功能改进在文档中详细说明，例如对与使用了 *tur.shp 的 Shape 载具其作为车体的 shp 文件应当使用什么样的序列、新的方式有哪些优势、旧的使用方式如何转为新的使用方式等内容，就像 静止的载具 那样。