Editing Posts

I've just recently begun using peach, and it's great! It would be really convenient if there was functionality to edit posts after they've been posted. I'm a CS student, and might clone the repo & look at the code after my semester is over. I noticed this on both desktop and the app.

未指定任何文件或测试。首先定位桌面端和 app 体验中 post 创建与显示的入口点，然后确定应如何表示和验证编辑功能；完成的标准是，已经发布的 post 可以在两种上下文中进行编辑。

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