Get npm run dev to work again

Signed-off-by: Sebastian Malton <sebastian@malton.name>

packages/ensure-binaries/package.json

@@ -7,7 +7,9 @@
   "scripts": {
     "clean": "rimraf dist/",
     "build": "swc ./src/index.ts -d ./dist/",
-    "prepare:dev": "npm run build",
+    "postbuild": "run-script-os",
+    "postbuild:nix": "chmod u+x ./dist/index.js",
+    "dev": "npm run build",
     "prepare": "npm run build"
   },
   "bin": {
@@ -38,6 +40,7 @@
     "@types/node": "^16.18.11",
     "@types/semver": "^7.3.13",
     "@types/tar-stream": "^2.2.2",
-    "rimraf": "^4.1.2"
+    "rimraf": "^4.1.2",
+    "run-script-os": "^1.1.6"
   }
 }