- Add auth guard to getLicServerConfig() - unauthenticated callers
now receive null config instead of DB values
- Remove non-existent 'superadmin' role from saveLicServerConfig()
check (only 'admin' exists per project schema)
- New migration: restrict settings table WRITE to admins only
(previously any authenticated user could overwrite licserver_api_key)
- Migration: add licserver_base_url/api_key cols to settings table
- New: lib/actions/licserver-config.ts (read/write/test server actions)
- Updated: proxy routes read config from DB with env-var fallback
- Updated: admin/einstellungen adds LicServer card with URL + API key
input, show/hide toggle, Save and Connection Test buttons
