- Remove User/Quota models; quota fields now live directly on APIKey
- Admin UI: login, API key management, settings (Ollama URL/model), proxy info display
- .env/.env.example: ADMIN_PASSWORD, PROXY_HOST/PORT, DATABASE_URL, APP_TZ
- Admin API runs on 127.0.0.1 only; proxy host/port configurable
- API keys support optional expires_at; verified against Europe/Berlin timezone
- Daily/monthly quota resets use Europe/Berlin midnight boundary
- Fix all tests to use new flat model; add expiry tests
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>