feat: add electron app.

website/src/react-app-env.d.ts

@@ -0,0 +1,19 @@
+/// <reference types="react-scripts" />
+
+declare module '*.less' {
+  const classes: { readonly [key: string]: string };
+  export default classes;
+}
+
+declare var VERSION: string;
+
+declare module '*.md' {
+  import { CodeBlockData } from 'markdown-react-code-preview-loader';
+  const src: CodeBlockData;
+  export default src;
+}
+
+declare module '*.md.css' {
+  const src: string;
+  export default src;
+}