Manyfold v0.117.0 is out, with a new organisation feature for merging together models (as in folders of files, not the 3d model files themselves); that should help to keep your archive under control!
Full release notes: https://manyfold.app/news/2025/07/08/release-v0-117-0.html
Join a public server: https://3dprint.social
Support us on OpenCollective: https://opencollective.com/manyfold