Production DemoNodeFactory: spawns a pw-loopback per node (via loopbackArgs,
the same audio-safe args the fader nodes use — node.autoconnect=false so a demo node never
grabs the default sink on its own) and waits until the node's source-side port appears in
pw-link -o. That probe is deliberately used instead of a full pw-dump: on a busy graph
the JSON dump can exceed the child-process buffer (silently truncating the probe), whereas
pw-link -o emits one small line per port.
Production DemoNodeFactory: spawns a
pw-loopbackper node (via loopbackArgs, the same audio-safe args the fader nodes use —node.autoconnect=falseso a demo node never grabs the default sink on its own) and waits until the node's source-side port appears inpw-link -o. That probe is deliberately used instead of a fullpw-dump: on a busy graph the JSON dump can exceed the child-process buffer (silently truncating the probe), whereaspw-link -oemits one small line per port.