Major Discovery:
- live-config scripts 0030-live-debconfig_passwd and 0030-user-setup were
  setting root password to '*' (locked) during boot
- This explains why SSH with configured password was failing
- Scripts were also trying to create 'user' account instead of using root

Solution:
- Created override-live-config-passwd.hook.chroot
- Replaces both password-related live-config scripts
- Preserves root password set during ISO creation
- Prevents account locking by live-config
- Forces LIVE_USERNAME=root instead of creating separate user

This completes the live-config override suite:
- inittab autologin (prevents user login prompt)
- password preservation (enables SSH with configured password)
- proper root account handling throughout boot process