- add tools/root-ssh-login.sh with interactive menu, --enable/--disable/--status flags, and sshd drop-in config management
- register root-ssh-login in lxs.sh dispatch and tools/index.sh interactive menu
- document new tool in README.md command reference and project structure
- add `tools/root-password.sh` to change root password interactively or generate a random one
- add `tools/update-server.sh` to run apt update/upgrade/autoremove/autoclean
- register both tools in `lxs.sh` dispatcher and `tools/index.sh` interactive menu
- document new tools in README.md
- move apps menu from inline lxs.sh function to apps/index.sh
- add tools/index.sh as entry point for tools menu
- rename system-tools.sh to system-infos.sh
- simplify help text to point users to the interactive menu
- update README directory tree to reflect new structure