Admin portal

Founder-only controls for tenants, pilots, and abuse response.

The internal admin portal is hidden behind `/admin` and uses founder/admin auth. It exposes tenant listing, limit overrides, pilot and refund state, API key inspection, and kill-switch execution.

GET    /api/v1/admin/overview
GET    /api/v1/admin/companies
GET    /api/v1/admin/companies/{company_id}/api-keys
PATCH  /api/v1/admin/companies/{company_id}/controls
POST   /api/v1/admin/companies/{company_id}/kill-switch
Open Admin PortalAuthentication