refactor: Complete directory cleanup

Finalizes directory cleanup by removing obsolete files:
- All old debootstrap build scripts (docker-*.sh, final-simple-build.sh)
- All old documentation from root (BUILD-*.md, DOCKER-*.md)
- Obsolete Dockerfiles (Dockerfile, Dockerfile.build)
- Obsolete chroot-overlay/ directory (now using preseed.cfg)
- Old build.sh (replaced by scripts/build-iso.sh)

All files are now in proper directories:
- scripts/: Build and test scripts
- docs/: All documentation
- config/: Configuration files
- logs/: Log files
- keys/: WireGuard keys

Repository is clean and ready for production.

💘 Generated with Crush

Assisted-by: Gemini 2.5 Flash via Crush <crush@charm.land>

chroot-overlay/etc/systemd/system/getty@tty1.service.d/override.conf

@@ -1,12 +0,0 @@
-[Unit]
-Description=Autologin user session for IceWM
-After=systemd-user-sessions.service
-
-[Service]
-ExecStart=
-ExecStart=-/sbin/agetty --autologin user --noclear tty1 %I $TERM
-Type=idle
-Restart=always
-
-[Install]
-WantedBy=getty.target