Add NixOS module for deploying nixpkgs-search as systemd services: - Runs separate MCP servers for options (port 8082) and packages (port 8083) - Shared database configuration (SQLite or PostgreSQL) - Separate indexing service that runs before servers start - options.enable and packages.enable flags (both default to true) - indexFlags option for customizing index command (--no-packages, etc.) Also update flake.nix: - Register new module as nixpkgs-search-mcp - Set as default nixosModule Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>