Update Calendar page

Rather than the current calendar page which is a little sad, keep the link to the google calendar, but have the events presented in a nicer format, include the ability to add documents to this for public viewing, such as the risk assessment and accessibility checklist for each event

首先定位当前的日历页面及其现有的 Google Calendar 链接。与维护者确认所需的事件展示方式和公开文档处理方式；当事件按约定的格式显示、Google Calendar 链接得以保留，并且每个事件都可以公开其文档时，即视为完成。

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