Pipeline Performance Tracking:
- pipeline-tracker.py records wall-clock timing per phase
- Token usage estimation (content + agent instructions + overhead)
- All 10 pipeline agents instrumented with phase-start/phase-end
- Phase 8 completion summary shows real timing + benchmark comparison

Multi-Backend I/O:
- 3 tracking backends: Google Sheets + Drive, Airtable, Local
- airtable-tracker.py — tracking + file delivery via attachments
- local-tracker.py — zero-auth JSON tracking + filesystem delivery
- backend-migrator.py — cross-backend data + file migration
- /cf:switch-backend skill for guided backend switching

Brand Setup Step G:
- Users choose tracking backend during brand onboarding
- Google and Airtable as primary options; Local if explicitly chosen
- Backend dispatch in Agents 08 + 09

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Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>