Migrate bin/*.js to TypeScript, use tsx

Author: Kocal

assets/package.json

@@ -20,8 +20,8 @@
         "css_source": "styles/live.css"
     },
     "scripts": {
-        "build": "node ../../../bin/build_package.js .",
-        "watch": "node ../../../bin/build_package.js . --watch",
+        "build": "tsx ../../../bin/build_package.ts .",
+        "watch": "tsx ../../../bin/build_package.ts . --watch",
         "test": "../../../bin/test_package.sh .",
         "check": "biome check",
         "ci": "biome ci"