Adds nixos-module.nix with services.oubliette options (enable, package,
settings, configFile) and a hardened systemd service. Exposes the module
as nixosModules.default in flake.nix.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Add core SSH server with password authentication, per-IP failure
tracking, credential memory with TTL, and static credential support.
Includes TOML config loading with validation, Ed25519 host key
auto-generation, and a Nix package output.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>