41e313bf36
Add infra-backup push/pull API for controller DR:
- POST /api/v1/infra-backup — controller pushes infrastructure snapshot
- GET /api/v1/infra-backup/{customer_id} — fresh controller pulls backup
- infra_backups SQLite table with per-customer snapshots
- Customer detail page shows infra backup status card
- README.md with full API docs and DR flow
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>