Deleted shares can not be reactivated

Need server-side: nextcloud/server#2192

### Actual behaviour
If you -deliberately or by accident- delete a share (folder or file) shared to you as read only in the Android app no option to reactivate/reinstantiate the folder is available to the user to whom the entity was shared.
The event of sharing the object is still visible in the activity protocol but clicking on the link fails.
The only option to get the shared object back is to revoke the share as sharing user and share again.

### Expected behaviour
It should be possible to reinstantiate the shared folder, e.g. via activity protocol or a special menu within settings.

### Steps to reproduce
1. Let user A share a folder with user B or a group user B belongs to with read only permissions
2. Log in user B to the Android client
3. User B deletes the shared folder in the Android client (I deleted “globally“, not only “local“ but I think it doesn't matter)
4. Open activity screen in Android client and select the (grayed out) deleted share

### Environment data
Android version:
Android 7.0

Device model:
Samsung S7

Stock or customized system:
Stock

Nextcloud app version:
3.1.0

Nextcloud server version:
13