feat(www): introduce monorepo

This change brings Turborepo monorepo to independently handle the marketing website, the docs website and any other future use cases for mutli-platform support. They are using internal @katanemo package handlers for the design system and logic.

apps/docs/next.config.ts

@@ -0,0 +1,8 @@
+import type { NextConfig } from "next";
+
+const nextConfig: NextConfig = {
+  /* config options here */
+};
+
+export default nextConfig;
+