AuthenticationRequired if authentication is missing.
ApiError with status 401 if authentication is invalid.
ApiError with status 403 if insufficient permissions.
Get public statistics.
Returns: total requests, total images, total tags, total artists.
Get admin statistics.
Returns detailed request statistics: requests today, daily history (last year), top users by requests, authenticated vs unauthenticated breakdown, API key vs JWT breakdown, plus all public stats.
Requires: Admin role.