Drop the startup deferral gate, its kill switch and the deferred loads:
they lowered renderer.ipcCallsToFirstCard but moved neither
spawnToFirstCardMs nor load->card beyond drift, and they grew
renderer.initialBytes. Keep the shared in-flight inventory read, inline
it in PlaylistsService with short property names, and copy the joiner's
result with structuredClone (the Electron renderer has it; the services
test setup polyfills it for jsdom).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>