docs: add CONTRIBUTING.md (umijs#1617)

CONTRIBUTING.md

@@ -0,0 +1,39 @@
+# How to contribute
+
+## Requirements
+
+[Node.js](https://nodejs.org/) >= 14, [PNPM](https://pnpm.io/) >= 7, [Rust](https://www.rust-lang.org/)
+
+After Rust is installed, add `wasm32-wasi`.
+
+```shell
+rustup target add wasm32-wasi
+```
+
+## Setup the repository locally
+
+1. Fork and clone the repository.
+
+```shell
+git clone https://github.com/<your name>/dumi.git
+cd dumi
+```
+
+2. Install all dependencies
+
+```shell
+pnpm install
+```
+
+> Due to the network download required by the scripts that need to be run during installation, you may need to set up a network proxy if an error occurs.
+
+Now you can start developing
+
+```shell
+pnpm dev
+pnpm docs:dev
+```
+
+## Submitting the Pull Request
+
+Submit a pull request from your topic branch to the master branch on the umijs/dumi repository.

README.md

@@ -10,13 +10,9 @@ dumi is a static site generator for component library development.
 
 To view more online examples and docs, please visit [dumi official site](https://d.umijs.org).
 
-## Development
+## Contributing
 
-```bash
-$ pnpm install
-$ pnpm dev
-$ pnpm docs:dev
-```
+See [CONTRIBUTING.md](CONTRIBUTING.md)
 
 ## Badge