docs: add setup part

Author: tjx666

README.md

@@ -11,10 +11,21 @@
 ## Features
 
 - github actions support publish extension to both vs marketplace and open vsx
-- auto generate changelog and publish github release
+- auto generate changelog and publish github release, make sure you enabled the write permission of github actions
 - pnpm/eslint/prettier/ling-staged/simple-git-hooks/stale-dep
 - use esbuild to bundle extension
 
+## Setup
+
+After fork this repository and clone it to local, run:
+
+```bash
+cd <your-extension-directory>
+npx setup-boilerplate
+```
+
+You can also just skip this step and adjust the boilerplate by yourself.
+
 ## Development
 
 Install dependencies by: