Extend 403 template to request access

No permission to access this resource
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Next step in the interaction:
Offer an input (button or whatever) to the user to make a request to access the resource.

There can be a number of ways to that.. config setting that shows the request form on all 403s and sends a notification to an (dedicated?) inbox, and/or if the resource has a dedicated inbox....

I said template in the title of this issue, but it'll act more like its own application (so that the server is not expected to process it like an HTML form) that sends a notification.

首先定位目前的 403 範本以及產生該範本的授權路徑。在選擇請求流程之前，檢查伺服器如何識別已登入使用者、目標資源和任何專用收件匣。完成的標準是：沒有權限的使用者可以提交存取請求，預期接收者會收到通知，但 payload 使設定和通知設計仍未確定。