v0.86.0

Changed

• Documents are stored more compactly (Discussion #332) — uploaded document files and calendar attachments are now kept as raw binary (BLOB) inside the SQLite database instead of Base64 text. This removes the ~33 % Base64 size overhead (saving roughly 25 % of the space used by locally stored documents) and cuts CPU/RAM work on every upload and download, which is most noticeable on low-powered devices like a Raspberry Pi. Existing databases are converted automatically on first start — no manual action is required — and WebDAV/DMS-backed documents are unaffected.