Set "private": true in package.json (#185)

This is meant to be a bool, not a string.

<https://docs.npmjs.com/cli/v10/configuring-npm/package-json#private>

Author: jarhill0

lib/install/package.json

@@ -1,4 +1,4 @@
 {
   "name": "app",
-  "private": "true"
+  "private": true
 }