feat: include type declaration file into package

fixes #217

Author: hudovisk

package.json

@@ -2,6 +2,7 @@
   "name": "react-optimize",
   "version": "1.0.2",
   "main": "lib/react-optimize.js",
+  "types": "lib/react-optimize.d.ts",
   "repository": "hudovisk/react-optimize",
   "license": "MIT",
   "files": [
@@ -36,6 +37,7 @@
     "babel-eslint": "^10.1.0",
     "babel-loader": "^8.1.0",
     "chai": "^4.2.0",
+    "copy-webpack-plugin": "^6.2.1",
     "cross-env": "^7.0.2",
     "enzyme": "^3.11.0",
     "enzyme-adapter-react-16": "^1.15.5",

webpack.config.js

@@ -1,4 +1,5 @@
 const path = require("path");
+const CopyPlugin = require("copy-webpack-plugin");
 
 module.exports = {
   mode: process.env.NODE_ENV === "production" ? "production" : "development",
@@ -25,5 +26,15 @@ module.exports = {
         }
       }
     ]
-  }
+  },
+  plugins: [
+    new CopyPlugin({
+      patterns: [
+        {
+          from: path.join(__dirname, "src/index.d.ts"),
+          to: path.join(__dirname, 'lib', 'react-optimize.d.ts'),
+        }
+      ]
+    })
+  ]
 };