Second field finding: a user-stopped engine came back when a song load
ran a rig_builder chain plan with startAudio:true - the executor calls
native startAudio directly in the main process, bypassing the IPC latch
check entirely (plan 6.1's second writer).
Decision (strict 8.3): only the device screen's user start resumes.
lease-bridge gains gateNativeAudio(), a proxy over the native accessor
that suppresses startAudio while latched (log-once telemetry line);
audio-bridge hands the executor the gated accessor.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>