rong>PassthroughCluster</strong> - The PassthroughCluster is a virtual cluster created
in the Envoy configuration when <code>global.outboundTrafficPolicy.mode</code> is set to
<code>ALLOW_ANY</code>. In this mode, all traffic to any external service external is allowed.
To implement this, the default virtual outbound listener at <code>0.0.0.0:15001</code>
which uses <code>SO_ORIGINAL_DST</code>, is setup as a TCP Proxy with the PassthroughCluster
as the static cluster.
The configuration for the PassthroughC