LocalHub constructor
port defaults to 0 = an ephemeral port (tests). fa hub serve
passes the well-known 8787 so zero-config clients
(ws://127.0.0.1:8787/ws) meet without configuration.
masterSecret password-protects the hub (docs/dap.md): every WS
upgrade must then carry the credential as Authorization: Bearer
Implementation
LocalHub({
this.port = 0,
this.bind = 'loopback',
this._masterSecret,
this._stateFile,
});