Replace system openclaw with portable flake

openclaw/flake.nix

@@ -0,0 +1,56 @@
+# nix develop
+{
+  description = "OpenClaw dev shell";
+
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs =
+    {
+      self,
+      nixpkgs,
+      flake-utils,
+    }:
+    flake-utils.lib.eachDefaultSystem (
+      system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+      in
+      {
+        devShells.default = pkgs.mkShell {
+          name = "openclaw-shell";
+
+          buildInputs = with pkgs; [
+            nodejs_22
+            git
+            curl
+            cmake
+          ];
+
+          shellHook = ''
+            echo "🦞 OpenClaw"
+            echo ""
+
+            # Set up local npm prefix to avoid permission issues
+            export NPM_CONFIG_PREFIX="$PWD/.npm-global"
+            export PATH="$NPM_CONFIG_PREFIX/bin:$PATH"
+
+            # Ensure the prefix directory exists
+            mkdir -p "$NPM_CONFIG_PREFIX/bin"
+
+            # Install openclaw if not already installed
+            if ! command -v openclaw &> /dev/null; then
+              echo "📦 Installing OpenClaw..."
+              npm install -g openclaw
+            fi
+
+            echo ""
+            echo "Run 'openclaw gateway' to start the gateway"
+            echo ""
+          '';
+        };
+      }
+    );
+}