Backend: DELETE /api/patterns/purge-all — removes all custom + backtested patterns
(source != 'builtin'), leaves Pattern Lab run history intact.
Frontend Config > Data Management:
- New PurgeButton for Pattern Library (custom_patterns table)
- Updated note: Trade Ideas are computed live from the Pattern Library (no separate table),
so purging patterns resets trade idea generation on next cycle.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>