- Settings → Maintenance gains a "Database maintenance" card: a "Run VACUUM
ANALYZE now" button (enqueues the maintenance task) plus a per-table bloat
readout (live/dead/dead%/last vacuum) from /api/admin/maintenance/db-stats.
- dbMaintenance store (loadStats / runVacuum) + test.
- Fix ruff I001: combine the two _sync_engine imports onto one line.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
