Feature Request: add wonnode landing page

[fkleedorfer]

Is your feature request related to a problem? Please describe.
People get confused: When they first configure a bot with 'https://hackathonnode.matchat.org/won', and something does not work, they tend to try 'https://hackathonnode.matchat.org/won' in the browser, which responds with a 403. So they think, there must be something wrong with the server. But there is nothing wrong with the server!

Describe the solution you'd like
Build a landing page for the node, with friendly, helpful information and a link to the node descriptor

Describe alternatives you've considered

• Doing it in the nginx - too complex
• redirect from server root to /resource - but a landing page is more versatile and we can include it in the onboarding process for developers

Additional context
Just saying, the current 403 response really throws people off

[quasarchimaere]

i would prefer the described alternative and redirect the root to /resource, because i have no idea what we should include into that landing page even, and that info will probably be stale after the initial change, so lets better redirect to /resource or /page -> because then we do not have to think of anything else