Add usage instructions, raw-link one-liner, config table, and
post-install steps for the helper script.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Creates a Debian 12 LXC container and sets up LinkVault as a systemd
service inside it, following the tteck/community-scripts pattern.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>