WebSocketTransportFactory

optional hook applied to ktor's TLSConfigBuilder for every transport this factory creates. It runs before platform trust is configured, so on Android a trust manager installed here is reached through the hostname-aware checkServerTrusted overload rather than bypassing it. Note that installing a trust manager replaces the platform's trust decision — network-security-config anchors, pinning, and Certificate Transparency policy then hold only insofar as that manager enforces them. Honoured on JVM, Android, Apple, and Linux; silently ignored on Windows (WinHttp has no TLS-config surface) and in the browser (which cannot influence trust). On Apple and Linux TLSConfigBuilder has no trustManager, so little is configurable there in practice.