OptionalfetchInjected for tests, and for a runtime whose global fetch you must wrap.
Optionalinit: RequestInitOptionalinit: RequestInitOptionaltimeoutMilliseconds to wait for a response.
OptionaltokenBearer token identifying the workload. Read it from the environment; never hard-code one. Omit it only against a local engine running without authentication.
OptionaluserOverrides the identifying header, which is useful when you want the audit log to distinguish one agent from another.
Options for the Client constructor.