update package.json to set main entry point and module type

Co-authored-by: Copilot <copilot@github.com>

package.json

@@ -2,7 +2,7 @@
   "name": "server",
   "version": "1.0.0",
   "description": "",
-  "main": "index.js",
+  "main": "dist/server.js",
   "scripts": {
     "dev": "tsx watch src/server.ts",
     "build": "tsc",
@@ -12,7 +12,7 @@
   "keywords": [],
   "author": "",
   "license": "ISC",
-  "type": "commonjs",
+  "type": "module",
   "dependencies": {
     "ws": "^8.20.0"
   },