init：创建后端项目框架，确保环境的基本运行

package.json

@@ -0,0 +1,31 @@
+{
+  "name": "pixel-game-server",
+  "version": "1.0.0",
+  "description": "A 2D pixel art game server built with NestJS",
+  "main": "dist/main.js",
+  "scripts": {
+    "dev": "nest start --watch",
+    "build": "nest build",
+    "start": "node dist/main.js",
+    "start:prod": "node dist/main.js"
+  },
+  "keywords": ["game", "pixel", "2d", "server", "nestjs"],
+  "author": "",
+  "license": "MIT",
+  "dependencies": {
+    "@nestjs/common": "^10.0.0",
+    "@nestjs/core": "^10.0.0",
+    "@nestjs/platform-express": "^10.0.0",
+    "@nestjs/websockets": "^10.0.0",
+    "@nestjs/platform-socket.io": "^10.0.0",
+    "reflect-metadata": "^0.1.13",
+    "rxjs": "^7.8.1"
+  },
+  "devDependencies": {
+    "@nestjs/cli": "^10.0.0",
+    "@nestjs/schematics": "^10.0.0",
+    "@types/node": "^20.0.0",
+    "ts-node": "^10.9.0",
+    "typescript": "^5.3.0"
+  }
+}