refactor: webpack configuration (#398)

* refactor: webpack configuration

* feat: webpack hot reloading

Co-authored-by: Johnny Almonte <johnny243@users.noreply.github.com>

webpack.dev.js

@@ -0,0 +1,17 @@
+const merge = require('webpack-merge');
+const config = require('./webpack.config.js');
+
+module.exports = merge(config, {
+  mode: 'development',
+  devtool: 'source-map',
+  devServer: {
+    publicPath: '/dist/',
+    proxy: {
+      '/extensions': {
+        target: 'http://localhost:3001',
+        pathRewrite: { '^/extensions': '/public/extensions' }
+      }
+    },
+    port: 3001
+  }
+});