Base URL of the QTSurfer API, e.g. https://api.qtsurfer.com/v1.
OptionalfetchInject a custom fetch (Node 20+, browser, or test mock).
Optionalinit: RequestInitOptionalinit: RequestInitOptionaltokenPre-obtained bearer token. When omitted, requests go out unauthenticated.
Use the authenticate() helper instead of this constructor if you want
the SDK to exchange an apikey for a JWT and refresh it on 401 for you.
Configuration for QTSurfer.