feat(api): implement API key management and authentication enhancements

- Added endpoints for managing API keys, including creation, retrieval, updating, and revocation.
- Introduced a new Auth session endpoint to retrieve current tenant and role information.
- Updated the authentication middleware to support API key-based authentication and track last used timestamps.
- Enhanced documentation to reflect new API key functionalities and usage guidelines.
- Improved logging for demo authentication scenarios.

docs/api.md

@@ -44,6 +44,12 @@
 - `GET|POST /v1/communities`
 - `GET|PATCH|DELETE /v1/communities/{id}`
 
+### API keys
+
+- `GET /v1/auth/session` — tenant и роль текущего ключа
+- `GET|POST /v1/api-keys` — список и создание (operator)
+- `GET|PATCH|DELETE /v1/api-keys/{id}`, `POST /v1/api-keys/{id}/rotate`
+
 ### Peers
 
 - `GET /v1/peers`, `POST /v1/peers`