Full-text search not working with server-side encryption

[mejo-]

Describe the bug
Full-text search seems to be broken when server-side encryption is enabled. The search request always returns an empty array (i.e. no results).

My suspicion is that indexing somehow is broken with encrypted Markdown files, but I didn't further look into it yet.

To Reproduce
Steps to reproduce the behavior:

1. Enable server-side encryption
2. Create a collective and a page with content
3. Run occ collectives:index to index the page for full-text search
4. Search for a word that is part of the page content
5. Watch the network request returning an empty array in ocs.data.pages

Server details:

• Collectives app version: 4.4.2
• Nextcloud version: latest master (35)