add poltergeist package and plugin

flake.nix

@@ -20,6 +20,7 @@
           sonoscli = pkgs.callPackage ./nix/pkgs/sonoscli.nix {};
           bird = pkgs.callPackage ./nix/pkgs/bird.nix {};
           peekaboo = pkgs.callPackage ./nix/pkgs/peekaboo.nix {};
+          poltergeist = pkgs.callPackage ./nix/pkgs/poltergeist.nix {};
         }
       );
 
@@ -30,6 +31,7 @@
         sonoscli = self.packages.${system}.sonoscli;
         bird = self.packages.${system}.bird;
         peekaboo = self.packages.${system}.peekaboo;
+        poltergeist = self.packages.${system}.poltergeist;
       });
     };
 }

nix/pkgs/poltergeist.nix

@@ -0,0 +1,37 @@
+{ lib, stdenv, fetchurl, watchman }:
+
+stdenv.mkDerivation {
+  pname = "poltergeist";
+  version = "2.1.1";
+
+  src = fetchurl {
+    url = "https://github.com/steipete/poltergeist/releases/download/v2.1.1/poltergeist-macos-universal-v2.1.1.tar.gz";
+    hash = "sha256-plQQjbB0QV7UY7U3ZdhfAZsAY/5m0G1E1WEgMm+elk8=";
+  };
+
+  dontConfigure = true;
+  dontBuild = true;
+
+  unpackPhase = ''
+    tar -xzf "$src"
+  '';
+
+  installPhase = ''
+    runHook preInstall
+    mkdir -p "$out/bin"
+    cp poltergeist "$out/bin/poltergeist"
+    cp polter "$out/bin/polter"
+    chmod 0755 "$out/bin/poltergeist" "$out/bin/polter"
+    runHook postInstall
+  '';
+
+  propagatedBuildInputs = [ watchman ];
+
+  meta = with lib; {
+    description = "Universal file watcher with auto-rebuild for any language or build system";
+    homepage = "https://github.com/steipete/poltergeist";
+    license = licenses.mit;
+    platforms = [ "aarch64-darwin" ];
+    mainProgram = "poltergeist";
+  };
+}

tools/poltergeist/flake.nix

@@ -0,0 +1,27 @@
+{
+  description = "clawdbot plugin: poltergeist";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+    root.url = "path:../..";
+  };
+
+  outputs = { self, nixpkgs, root }:
+    let
+      system = "aarch64-darwin";
+      pkgs = import nixpkgs { inherit system; };
+      poltergeist = root.packages.${system}.poltergeist;
+    in {
+      packages.${system}.poltergeist = poltergeist;
+
+      clawdbotPlugin = {
+        name = "poltergeist";
+        skills = [ ./skills/poltergeist ];
+        packages = [ poltergeist ];
+        needs = {
+          stateDirs = [];
+          requiredEnv = [];
+        };
+      };
+    };
+}

tools/poltergeist/skills/poltergeist/SKILL.md

@@ -0,0 +1,9 @@
+---
+name: poltergeist
+description: File watcher with auto-rebuild for any language or build system.
+---
+
+Use the `poltergeist` and `polter` CLIs to watch and run builds.
+
+Example:
+- poltergeist --help