fix: skip postinstall git clean when not in a git repository

Author: angeldeejay

package-lock.json

@@ -41,6 +41,7 @@
 		"css",
 		"defaultmodules",
 		"js",
+		"scripts",
 		"serveronly",
 		"translations",
 		"favicon.svg",
@@ -49,7 +50,7 @@
 	"sideEffects": true,
 	"scripts": {
 		"config:check": "node js/check_config.js",
-		"postinstall": "git clean -df fonts vendor modules/default",
+		"postinstall": "node scripts/postinstall.js",
 		"install-mm": "npm install --no-audit --no-fund --no-update-notifier --only=prod --omit=dev",
 		"install-mm:dev": "npm install --no-audit --no-fund --no-update-notifier && npx playwright install chromium",
 		"lint:css": "stylelint 'css/**/*.css' 'defaultmodules/**/*.css' --fix",

package.json

@@ -0,0 +1,24 @@
+#!/usr/bin/env node
+/**
+ * postinstall.js
+ *
+ * Runs `git clean -df fonts vendor modules/default` only when executed
+ * inside a git repository. When magicmirror is installed as an npm
+ * dependency in another project, the working directory is not a git
+ * repo and the clean step is silently skipped.
+ *
+ * Cross-platform (Linux, macOS, Windows).
+ */
+
+"use strict";
+
+const { execSync } = require("child_process");
+
+try {
+	execSync("git rev-parse --git-dir", { stdio: "ignore" });
+} catch {
+	// Not a git repository — skip git clean.
+	process.exit(0);
+}
+
+execSync("git clean -df fonts vendor modules/default", { stdio: "inherit" });