/**
 * `crypto.randomUUID()` is only exposed in secure contexts, so a browser client served over
 * plain http - a LAN tool, a device on the local network, an intranet page - has a `crypto`
 * object but no `randomUUID` on it, and calling it throws.
 *
 * These ids only have to be unique within a connection (request ids, packet ids, callback
 * ids); they are not secrets and nothing authenticates against them, so degrading to
 * `Math.random` when no CSPRNG is reachable is safe.
 */
export declare function randomUUID(): string;