feat: implement real uptime monitoring, alerts, admin dashboard, billing & usage tracking
- Uptime service: real HTTP HEAD checks with response time tracking
- Alert engine: evaluates scan results, auto-resolves recovered alerts
- Notifications: Resend email + webhook delivery
- Admin dashboard: system stats, user CRUD, org management (role-protected)
- Billing: tier limits (free/starter/pro/enterprise), usage tracking API
- Competitor analysis: real Lighthouse comparison + response time
- Tests: 11 backend + 11 frontend = 22 total tests passing
- Database: added competitor_metrics, alert_configurations tables
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Dennis
0d2aef07bc