Reports whether something is listening at a berth's WebSocket address, by a
plain TCP connect — no WebSocket handshake, so this stays within the daemon
package (which has no client). It is the liveness check daemon_launch uses
to refuse starting a rival for an identity that is already hosted; a surface's
resolver uses a stronger handshake probe for attach.
Parameters
url: string
A ws://host:port berth URL.
timeoutMs: number = 500
How long to wait for the TCP connect (default 500 ms).
Reports whether something is listening at a berth's WebSocket address, by a plain TCP connect — no WebSocket handshake, so this stays within the daemon package (which has no client). It is the liveness check
daemon_launchuses to refuse starting a rival for an identity that is already hosted; a surface's resolver uses a stronger handshake probe for attach.