Astro.response.headers 不能重新分配。

AstroResponseHeadersReassigned：可以在 Astro.response.headers 中添加和删除单个标题，但不能将其完全替换为 Headers 的另一个实例。

¥AstroResponseHeadersReassigned: Individual headers can be added to and removed from Astro.response.headers, but it must not be replaced with another instance of Headers altogether.

什么地方出了错？

¥What went wrong?

当将值设置为 ResponseInit 对象上的 headers 字段时抛出，该对象可用作 Astro.response。

¥Thrown when a value is being set as the headers field on the ResponseInit object available as Astro.response.