fix: fix document error for frontend

pinry-spa/README.md

@@ -1,23 +1,26 @@
 # pinry-spa
 
 ## Project setup
+This project requires `NodeJS@18`.
+
 ```
-yarn install
+npm install -g "pnpm==9.11.0"
+pnpm install
 ```
 
 ### Compiles and hot-reloads for development
 ```
-yarn serve
+pnpm serve
 ```
 
 ### Compiles and minifies for production
 ```
-yarn build
+pnpm build
 ```
 
 ### Lints and fixes files
 ```
-yarn lint
+pnpm lint
 ```
 
 ### Customize configuration