chore: add clipper extension package (#2281)

packages/clipper/webpack.config.dev.js

@@ -0,0 +1,9 @@
+const { merge } = require('webpack-merge')
+const config = require('./webpack.config.js')
+
+module.exports = (env, argv) => {
+  return merge(config(env, argv), {
+    mode: 'development',
+    devtool: 'cheap-module-source-map',
+  })
+}