refactor: migrate to pnpm monorepo with Payload CMS backend and Astro frontend to support scalable website development and AI-assisted workflows

package.json

@@ -0,0 +1,14 @@
+{
+  "name": "enchun-monorepo",
+  "private": true,
+  "packageManager": "pnpm@10.17.0",
+  "scripts": {
+    "dev": "turbo run dev --parallel",
+    "build": "turbo run build",
+    "lint": "turbo run lint",
+    "test": "turbo run test"
+  },
+  "devDependencies": {
+    "turbo": "^2.0.5"
+  }
+}