- withSuperAdmin() HOF: checks isSuperAdmin from session, returns 401/403
- GET /api/admin/tenants: lists all tenants with userCount, subscriberCount
- GET /api/admin/tenants/[id]: single tenant detail with users list
- POST /api/admin/tenants/[id]/suspend: suspend/activate with 7-day grace
- prisma/seed.ts: add Test ISP 2 tenant and admin2@demo.com for isolation tests
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>