- rewrite gmail-sync handler: mbsync downloads to local Maildir, then import to sqlite - add app password field to google integration config and API - gmail sync section independent from oauth in settings UI - live mbsync progress streaming to job status - recoverable failure email with instructions for overquota/auth errors - sync meta persisted to job on failure for richer notifications Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>