feat: add missing packages and programs to base cli-tools

- packages.nix: essential packages (jq, ripgrep, fd, htop, coreutils,
  lazygit, httpie, just, devenv, gcc, go, sqlite, sqlite-vec, nix-index,
  nix-update, progress, comma, fabric-ai, llm, basecamp, hyprpaper-random,
  libnotify, trash-cli, unzip, zip, yazi)
- bat.nix: bat with nix-colors derived syntax theme
- carapace.nix: multi-shell completion (fish, nushell, bash)
- direnv.nix: automatic env loading with nix-direnv
- eza.nix: modern ls with icons, git status, long format
- lf.nix: terminal file manager with bat preview
- zoxide.nix: smarter cd with fish and nushell integration
- zellij-ps.nix: project session manager wrapping cli.zellij-ps

home/base/cli-tools/direnv.nix

@@ -0,0 +1,19 @@
+# Direnv — automatic environment loading with nix-direnv integration.
+{
+  config,
+  lib,
+  ...
+}:
+with lib; let
+  cfg = config.base.cliTools.direnv;
+in {
+  options.base.cliTools.direnv.enable = mkEnableOption "enable direnv with nix-direnv";
+
+  config = mkIf cfg.enable {
+    programs.direnv = {
+      enable = true;
+      enableNushellIntegration = true;
+      nix-direnv.enable = true;
+    };
+  };
+}