tests/frame-container/frame-image.sh extracts rootfs-A from Valve's Frame
recovery image (steamdeck-images.steamos.cloud/recovery), mounts it read-only
with a throwaway writable layer and starts the image's own sshd, so the iPhone
app can pair with and run its server on the real SteamOS for Frame userland.
Verified: password pairing then key login in the image's sshd log, the power
password check through the image's sudo, status reading SteamOS 0.3.0.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
