chore: allow separate server url/deploy url for frontend app

At the moment we feed in a single path to the frontend app for the server, api and frontend app deployed path. It should be easy to specify all 3 separately - they will be identical on the production config, just different in the watch mode file.

It should make no difference to the deployed app, but in the watch task it will be possible to search in the explore page and navigate between pages in the frontend app.