poll for real SSH banner instead of TCP accept (qemu's user-mode nic accepts before guest sshd is listening), preserve qemu log on abnormal exit for inspection, use a throwaway ed25519 key since the guest accepts any key.
poll for real SSH banner instead of TCP accept (qemu's user-mode nic accepts before guest sshd is listening), preserve qemu log on abnormal exit for inspection, use a throwaway ed25519 key since the guest accepts any key.