fix: create /dev/console in initramfs + suppress ACPI noise
- Create /dev/console, /dev/null, /dev/zero, /dev/tty in initramfs
(fixes "Warning: unable to open an initial console" boot failure)
- Set loglevel=1 + quiet to suppress ThinkPad ACPI warnings
- Audio: fix sample playback race condition on recording stop
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>