Add SSR React application to HAP

Add a channel to the HAP, hosting a server-side rendered React application.

Generate server-side rendered React app based on same SPA code base
Start it when the HAP starts. Use URL Rewriter plugin to proxy requests.

Ensure that the application integrates with the Channel Manager for basic management (containers+components, menu editing and content creation/editing).

For SSR web applications, the (external) server is the client/consumer of the PageModel API, through the SPA SDK.

Add automated smoke tests to ensure that this way of integrating web applications with brXM keeps working.