Turn treatments to match bend on flags

On a shield the bend is always 45 so we turn (some) treatments to match.

O a flag bends are at an abitrary angle depending on the proportions. We should calculate the appropriate angle and turn the same set of treatments accordingly.


(For the same reason we don't currently support charges "on a bend" in flags as we don't have the angle)

首先跟踪盾牌现有的处理旋转逻辑，以及确定旗帜弯曲几何形状的代码。根据旗帜的比例计算其弯曲角度，并应用相同的处理旋转行为；完成标准是处理结果与旗帜的弯曲相匹配，同时盾牌行为保持不变。

由索引模型根据 Issue 内容生成。