Can't re-add deleted feed via API

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Explain the Problem

A feed that has been removed in the UI can not be re-added via the API (as it appears to still exist?). I haven't checked the DB, presumably it's still there.

Steps to Reproduce

Explain what you did to encounter the issue

1. Remove a feed from the UI
2. Use API to attempt to add the feed
3. Recieve status code 409 with message Feed with this URL exists

System Information

• News app version: 25.1.0
• Nextcloud version: 29.0.9
• Browser and version: Firefox 133.0
• Cron type: Cron
• PHP version: 8.3.14
• Database and version: MariaDB 10.5.23
• OS and version: Client or server? Either way Debian, 11 on server, testing on client.

edit: further server details

Start by reproducing the API add request after removing the feed in the UI, then trace the feed creation and deletion paths that produce the Feed with this URL exists response. Done means a feed removed through the UI can be added again through the API without a 409, while genuinely existing feeds still return the conflict.