Add 6 new tests covering document sort (name/size), FTS search cross-user
isolation, credentials_enc exclusion from all responses, and MinIO object
cleanup on user deletion.
Fix FTS try/except misplacement in api/documents.py — was wrapping the ORM
statement builder (never raises) instead of the execute call, causing HTTP 500
on SQLite test env. Now falls back to unfiltered results when @@ unsupported.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>