Use 'X-NC-Skip-Trashbin' header to delete files without trashbin when cleaning up Nextcloud WebDAV backups

Prefacing with the fact that backing up my phone to my Nextcloud instance with WebDAV has been sturdy and solid for a while, I have the annoyance that Seedvault sends a lot of files to the trash bin when cleaning up backups. This clogs up the trash bin with files that aren't in my retention policy anymore, making it difficult to browse the bin normally. I don't want to completely disable trash bin retention, I still want that option for my user files.

Nextcloud now supports WebDAV DELETEs without trashbin with a X-NC-Skip-Trashbin header.

• Issue
• PR

It would be awesome to have Seedvault pass this custom header on DELETEs, at least as an opt-in. An expert setting for "custom WebDAV headers" would also work.