Read the calling API key's authorized sources and result origin

Free, header-only X-API-Key authentication. Returns only granted public source names and the configured signed-result storage origin (null if unavailable). No account ID, key ID, secret or storage credentials are returned. Local MCP revalidates this endpoint before every tool discovery and call, including cached result reads. No query parameters or request body are accepted. All /api-access routes share 120 requests per minute per client IP and return Cache-Control private, no-store. Normal key last-used tracking still occurs.